feat(02-03): TOTP enrollment flow, backup codes, AccountView, ConfirmBlock

- TotpEnrollment.vue: three-step enrollment (setup → verify → backup-codes); emits 'enrolled'
- BackupCodesDisplay.vue: 2-column grid, copy-all clipboard, acknowledgment checkbox
- ConfirmBlock.vue: reusable inline confirmation block with 'confirmed'/'cancelled' emits
- AccountView.vue: TOTP section (enrollment or disable), change-password with breach/wrong-pw error handling, sign-out-all with ConfirmBlock
- npm run build exits 0

frontend/src/components/auth/BackupCodesDisplay.vue

@@ -0,0 +1,84 @@
+<template>
+  <div class="space-y-4">
+    <div>
+      <h3 class="text-xl font-semibold text-gray-900 mb-1">Save your backup codes</h3>
+      <p class="text-sm text-gray-500">
+        Store these codes somewhere safe. Each can only be used once if you lose access to your authenticator app.
+      </p>
+    </div>
+
+    <!-- 2-column grid of backup codes -->
+    <div class="grid grid-cols-2 gap-2">
+      <div
+        v-for="code in codes"
+        :key="code"
+        class="font-mono text-sm text-gray-800 bg-gray-50 border border-gray-200 rounded-md px-3 py-2 text-center"
+      >
+        {{ code }}
+      </div>
+    </div>
+
+    <!-- Copy all button -->
+    <button
+      type="button"
+      @click="copyAll"
+      class="flex items-center gap-2 text-sm font-semibold text-indigo-600 hover:text-indigo-700 transition-colors"
+    >
+      <!-- Clipboard icon -->
+      <svg class="w-4 h-4" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor">
+        <path stroke-linecap="round" stroke-linejoin="round" d="M15.666 3.888A2.25 2.25 0 0013.5 2.25h-3c-1.03 0-1.9.693-2.166 1.638m7.332 0c.055.194.084.4.084.612v0a.75.75 0 01-.75.75H9a.75.75 0 01-.75-.75v0c0-.212.03-.418.084-.612m7.332 0c.646.049 1.288.11 1.927.184 1.1.128 1.907 1.077 1.907 2.185V19.5a2.25 2.25 0 01-2.25 2.25H6.75A2.25 2.25 0 014.5 19.5V6.257c0-1.108.806-2.057 1.907-2.185a48.208 48.208 0 011.927-.184" />
+      </svg>
+      {{ copied ? 'Copied' : 'Copy all codes' }}
+    </button>
+
+    <!-- Acknowledgment checkbox -->
+    <div class="flex items-start gap-3 pt-2">
+      <input
+        id="backup-codes-ack"
+        v-model="acknowledged"
+        type="checkbox"
+        class="mt-0.5 rounded border-gray-300 text-indigo-600 focus:ring-indigo-500"
+      />
+      <label for="backup-codes-ack" class="text-sm text-gray-700 cursor-pointer">
+        I have saved these codes in a secure place. I understand they will not be shown again.
+      </label>
+    </div>
+
+    <!-- Enable 2FA CTA — disabled until acknowledged -->
+    <button
+      type="button"
+      @click="acknowledged && $emit('acknowledged')"
+      :disabled="!acknowledged"
+      class="w-full px-6 py-3 bg-indigo-600 text-white rounded-lg text-sm font-semibold hover:bg-indigo-700 transition-colors min-h-[44px]"
+      :class="!acknowledged ? 'opacity-50 cursor-not-allowed' : ''"
+    >
+      Enable two-factor authentication
+    </button>
+  </div>
+</template>
+
+<script setup>
+import { ref } from 'vue'
+
+const props = defineProps({
+  codes: {
+    type: Array,
+    required: true,
+  },
+})
+
+defineEmits(['acknowledged'])
+
+const acknowledged = ref(false)
+const copied = ref(false)
+
+async function copyAll() {
+  try {
+    await navigator.clipboard.writeText(props.codes.join('\n'))
+    copied.value = true
+    setTimeout(() => { copied.value = false }, 2000)
+  } catch {
+    // Clipboard API may fail in some environments — fail silently
+  }
+}
+</script>

frontend/src/components/auth/TotpEnrollment.vue

@@ -0,0 +1,181 @@
+<template>
+  <div class="space-y-4">
+
+    <!-- Step: setup — initial prompt to begin enrollment -->
+    <template v-if="step === 'setup'">
+      <div class="space-y-3">
+        <p class="text-sm text-gray-600">
+          Two-factor authentication adds an extra layer of security. You will need an authenticator app (e.g. Google Authenticator, Authy) on your phone.
+        </p>
+        <button
+          type="button"
+          @click="startSetup"
+          :disabled="loading"
+          class="flex items-center gap-2 px-6 py-2.5 bg-indigo-600 text-white rounded-lg text-sm font-semibold hover:bg-indigo-700 transition-colors disabled:opacity-75 min-h-[44px]"
+        >
+          <AppSpinner v-if="loading" />
+          {{ loading ? 'Setting up…' : 'Set up two-factor authentication' }}
+        </button>
+        <p v-if="error" class="mt-1 text-xs text-red-600">{{ error }}</p>
+      </div>
+    </template>
+
+    <!-- Step: verify — show QR/secret and accept code -->
+    <template v-else-if="step === 'verify'">
+      <div class="space-y-4">
+        <div>
+          <p class="text-sm text-gray-600 mb-3">
+            Open your authenticator app and scan this QR code, or enter the key manually.
+          </p>
+
+          <!-- QR code — rendered via provisioning URI link (no QR library dependency) -->
+          <div class="bg-white border border-gray-200 rounded-xl p-6 flex flex-col items-center gap-4">
+            <p class="text-xs text-gray-500 text-center">Scan with your authenticator app using the link below, or enter the secret key manually:</p>
+            <a
+              :href="qrUri"
+              class="text-sm font-semibold text-indigo-600 hover:text-indigo-700 underline break-all text-center"
+              target="_blank"
+              rel="noopener noreferrer"
+            >
+              Open in authenticator app
+            </a>
+          </div>
+        </div>
+
+        <!-- Manual secret display -->
+        <div>
+          <p class="text-xs text-gray-500 mb-1 font-semibold">Or enter this secret key manually:</p>
+          <div class="flex items-center gap-2">
+            <code
+              class="font-mono text-sm text-gray-700 bg-gray-50 px-3 py-2 rounded-md border border-gray-200 break-all flex-1"
+            >{{ secret }}</code>
+            <button
+              type="button"
+              @click="copySecret"
+              aria-label="Copy secret key"
+              class="text-gray-400 hover:text-gray-600 transition-colors flex-shrink-0"
+            >
+              <svg class="w-4 h-4" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor">
+                <path stroke-linecap="round" stroke-linejoin="round" d="M15.666 3.888A2.25 2.25 0 0013.5 2.25h-3c-1.03 0-1.9.693-2.166 1.638m7.332 0c.055.194.084.4.084.612v0a.75.75 0 01-.75.75H9a.75.75 0 01-.75-.75v0c0-.212.03-.418.084-.612m7.332 0c.646.049 1.288.11 1.927.184 1.1.128 1.907 1.077 1.907 2.185V19.5a2.25 2.25 0 01-2.25 2.25H6.75A2.25 2.25 0 014.5 19.5V6.257c0-1.108.806-2.057 1.907-2.185a48.208 48.208 0 011.927-.184" />
+              </svg>
+            </button>
+          </div>
+          <p v-if="secretCopied" class="mt-1 text-xs text-green-600">Copied!</p>
+        </div>
+
+        <!-- Verification code input -->
+        <div>
+          <label class="block text-sm font-semibold text-gray-700 mb-1">
+            Enter the 6-digit code from your authenticator app
+          </label>
+          <input
+            v-model="verifyCode"
+            type="text"
+            inputmode="numeric"
+            maxlength="6"
+            placeholder="000000"
+            autocomplete="one-time-code"
+            class="block w-36 rounded-lg px-3 py-3 text-sm border transition-colors focus:ring-2 focus:outline-none"
+            :class="error
+              ? 'border-red-500 ring-red-500 focus:ring-red-500 focus:border-red-500'
+              : 'border-gray-300 focus:ring-indigo-500 focus:border-indigo-500'"
+          />
+          <p v-if="error" class="mt-1 text-xs text-red-600">{{ error }}</p>
+          <p v-if="verified" class="mt-1 text-xs text-green-600 flex items-center gap-1">
+            <!-- Checkmark icon -->
+            <svg class="w-4 h-4" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="1.5" stroke="currentColor">
+              <path stroke-linecap="round" stroke-linejoin="round" d="M4.5 12.75l6 6 9-13.5" />
+            </svg>
+            Authenticator connected.
+          </p>
+        </div>
+
+        <button
+          type="button"
+          @click="confirmEnrollment"
+          :disabled="loading || verifyCode.length !== 6"
+          class="flex items-center gap-2 px-6 py-2.5 bg-indigo-600 text-white rounded-lg text-sm font-semibold hover:bg-indigo-700 transition-colors disabled:opacity-75 min-h-[44px]"
+        >
+          <AppSpinner v-if="loading" />
+          {{ loading ? 'Verifying…' : 'Verify code' }}
+        </button>
+      </div>
+    </template>
+
+    <!-- Step: backup-codes — show BackupCodesDisplay -->
+    <template v-else-if="step === 'backup-codes'">
+      <BackupCodesDisplay
+        :codes="backupCodes"
+        @acknowledged="finishEnrollment"
+      />
+    </template>
+
+  </div>
+</template>
+
+<script setup>
+import { ref } from 'vue'
+import * as api from '../../api/client.js'
+import AppSpinner from '../ui/AppSpinner.vue'
+import BackupCodesDisplay from './BackupCodesDisplay.vue'
+
+const emit = defineEmits(['enrolled'])
+
+const step = ref('setup')
+const qrUri = ref('')
+const secret = ref('')
+const verifyCode = ref('')
+const backupCodes = ref([])
+const error = ref(null)
+const loading = ref(false)
+const verified = ref(false)
+const secretCopied = ref(false)
+
+async function startSetup() {
+  loading.value = true
+  error.value = null
+  try {
+    const data = await api.totpSetup()
+    qrUri.value = data.provisioning_uri
+    secret.value = data.secret
+    step.value = 'verify'
+  } catch (e) {
+    error.value = e.message
+  } finally {
+    loading.value = false
+  }
+}
+
+async function confirmEnrollment() {
+  loading.value = true
+  error.value = null
+  try {
+    const data = await api.totpEnable(verifyCode.value)
+    backupCodes.value = data.backup_codes
+    verified.value = true
+    // Brief success flash before transitioning to backup codes screen
+    setTimeout(() => {
+      step.value = 'backup-codes'
+    }, 800)
+  } catch (e) {
+    error.value = 'Incorrect code. Try again.'
+    verifyCode.value = ''
+  } finally {
+    loading.value = false
+  }
+}
+
+function finishEnrollment() {
+  emit('enrolled')
+}
+
+async function copySecret() {
+  try {
+    await navigator.clipboard.writeText(secret.value)
+    secretCopied.value = true
+    setTimeout(() => { secretCopied.value = false }, 2000)
+  } catch {
+    // Fail silently
+  }
+}
+</script>

frontend/src/components/ui/ConfirmBlock.vue

@@ -0,0 +1,45 @@
+<template>
+  <div class="space-y-3">
+    <p class="text-sm text-gray-700">{{ message }}</p>
+    <div class="flex gap-3 items-center">
+      <button
+        type="button"
+        @click="$emit('cancelled')"
+        class="text-sm text-gray-600 hover:text-gray-800"
+      >
+        {{ cancelLabel }}
+      </button>
+      <button
+        type="button"
+        @click="$emit('confirmed')"
+        class="flex items-center gap-2 px-4 py-2 rounded-lg text-sm font-semibold transition-colors min-h-[44px]"
+        :class="confirmClass || 'bg-red-600 hover:bg-red-700 text-white'"
+      >
+        {{ confirmLabel }}
+      </button>
+    </div>
+  </div>
+</template>
+
+<script setup>
+defineProps({
+  message: {
+    type: String,
+    required: true,
+  },
+  confirmLabel: {
+    type: String,
+    default: 'Confirm',
+  },
+  cancelLabel: {
+    type: String,
+    default: 'Cancel',
+  },
+  confirmClass: {
+    type: String,
+    default: '',
+  },
+})
+
+defineEmits(['confirmed', 'cancelled'])
+</script>

frontend/src/views/AccountView.vue

@@ -3,7 +3,8 @@
     <h2 class="text-2xl font-semibold text-gray-900 mb-6">Account settings</h2>
 
     <div class="space-y-6">
-      <!-- Account information -->
+
+      <!-- 1. Account information -->
       <section class="bg-white border border-gray-200 rounded-xl p-6">
         <h3 class="font-semibold text-gray-800 mb-4">Account information</h3>
         <div class="space-y-2 text-sm text-gray-700">
@@ -22,7 +23,50 @@
         </div>
       </section>
 
-      <!-- Change password -->
+      <!-- 2. Two-factor authentication -->
+      <section class="bg-white border border-gray-200 rounded-xl p-6">
+        <h3 class="font-semibold text-gray-800 mb-4">Two-factor authentication</h3>
+
+        <!-- TOTP enabled: show status + disable option -->
+        <template v-if="authStore.user?.totp_enabled">
+          <div class="flex items-center gap-3 mb-4">
+            <span class="inline-flex items-center gap-1.5 text-sm text-green-700 font-semibold">
+              <!-- Checkmark -->
+              <svg class="w-4 h-4" xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke-width="2" stroke="currentColor">
+                <path stroke-linecap="round" stroke-linejoin="round" d="M4.5 12.75l6 6 9-13.5" />
+              </svg>
+              Enabled
+            </span>
+          </div>
+
+          <template v-if="!confirmDisable2fa">
+            <button
+              type="button"
+              @click="confirmDisable2fa = true"
+              class="text-sm px-4 py-2 border border-red-300 text-red-600 rounded-lg hover:bg-red-50 transition-colors"
+            >
+              Disable 2FA
+            </button>
+          </template>
+          <template v-else>
+            <ConfirmBlock
+              message="This will disable two-factor authentication. Your account will be less secure."
+              confirm-label="Disable 2FA"
+              cancel-label="Keep enabled"
+              @confirmed="disableTotp"
+              @cancelled="confirmDisable2fa = false"
+            />
+            <p v-if="totpError" class="mt-2 text-xs text-red-600">{{ totpError }}</p>
+          </template>
+        </template>
+
+        <!-- TOTP not enabled: show enrollment component -->
+        <template v-else>
+          <TotpEnrollment @enrolled="onTotpEnrolled" />
+        </template>
+      </section>
+
+      <!-- 3. Change password -->
       <section class="bg-white border border-gray-200 rounded-xl p-6">
         <h3 class="font-semibold text-gray-800 mb-4">Change password</h3>
 
@@ -33,29 +77,49 @@
               v-model="currentPassword"
               type="password"
               required
-              class="block w-full rounded-lg px-3 py-3 text-sm border border-gray-300 bg-white text-gray-900 focus:ring-2 focus:ring-indigo-500 focus:border-indigo-500 focus:outline-none"
+              autocomplete="current-password"
+              class="block w-full rounded-lg px-3 py-3 text-sm border bg-white text-gray-900 transition-colors focus:ring-2 focus:outline-none"
+              :class="passwordError && passwordError.includes('Current')
+                ? 'border-red-500 focus:ring-red-500 focus:border-red-500'
+                : 'border-gray-300 focus:ring-indigo-500 focus:border-indigo-500'"
             />
+            <p
+              v-if="passwordError && passwordError.includes('Current')"
+              class="mt-1 text-xs text-red-600"
+            >
+              {{ passwordError }}
+            </p>
           </div>
+
           <div>
             <label class="block text-sm font-semibold text-gray-700 mb-1">New password</label>
             <input
               v-model="newPassword"
               type="password"
               required
-              class="block w-full rounded-lg px-3 py-3 text-sm border border-gray-300 bg-white text-gray-900 focus:ring-2 focus:ring-indigo-500 focus:border-indigo-500 focus:outline-none"
+              autocomplete="new-password"
+              class="block w-full rounded-lg px-3 py-3 text-sm border bg-white text-gray-900 transition-colors focus:ring-2 focus:outline-none"
+              :class="passwordError && !passwordError.includes('Current')
+                ? 'border-red-500 focus:ring-red-500 focus:border-red-500'
+                : 'border-gray-300 focus:ring-indigo-500 focus:border-indigo-500'"
             />
             <PasswordStrengthBar :password="newPassword" />
           </div>
 
-          <div v-if="passwordError" class="p-3 rounded-lg bg-red-50 border border-red-200 text-sm text-red-700">
+          <!-- Form-level error (e.g. breach check, strength failure) -->
+          <div
+            v-if="passwordError && !passwordError.includes('Current')"
+            class="p-3 rounded-lg bg-red-50 border border-red-200 text-sm text-red-700"
+          >
             {{ passwordError }}
           </div>
+
           <div v-if="passwordSuccess" class="text-sm text-green-600">{{ passwordSuccess }}</div>
 
           <button
             type="submit"
             :disabled="changingPassword"
-            class="flex items-center gap-2 px-6 py-2.5 bg-indigo-600 text-white rounded-lg text-sm font-semibold hover:bg-indigo-700 transition-colors disabled:opacity-75"
+            class="flex items-center gap-2 px-6 py-2.5 bg-indigo-600 text-white rounded-lg text-sm font-semibold hover:bg-indigo-700 transition-colors disabled:opacity-75 min-h-[44px]"
           >
             <AppSpinner v-if="changingPassword" />
             {{ changingPassword ? 'Updating…' : 'Update password' }}
@@ -63,12 +127,13 @@
         </form>
       </section>
 
-      <!-- Sessions -->
+      <!-- 4. Sessions — sign out all devices -->
       <section class="bg-white border border-gray-200 rounded-xl p-6">
         <h3 class="font-semibold text-gray-800 mb-4">Sessions</h3>
 
         <template v-if="!confirmSignOutAll">
           <button
+            type="button"
             @click="confirmSignOutAll = true"
             class="text-sm px-4 py-2 border border-red-300 text-red-600 rounded-lg hover:bg-red-50 transition-colors"
           >
@@ -77,27 +142,28 @@
         </template>
 
         <template v-else>
-          <p class="text-sm text-gray-700 mb-3">
-            This will sign you out of all devices, including this one. You will need to sign in again.
-          </p>
-          <div class="flex gap-3">
-            <button
-              @click="confirmSignOutAll = false"
-              class="text-sm text-gray-600 hover:text-gray-800"
+          <ConfirmBlock
+            message="This will sign you out of all devices, including this one. You will need to sign in again."
+            confirm-label="Sign out all devices"
+            cancel-label="Keep signed in"
+            @confirmed="signOutAll"
+            @cancelled="confirmSignOutAll = false"
           >
-              Keep signed in
-            </button>
+            <template #confirm-button>
               <button
+                type="button"
                 @click="signOutAll"
                 :disabled="signingOutAll"
-              class="flex items-center gap-2 px-4 py-2 bg-red-600 hover:bg-red-700 text-white text-sm font-semibold rounded-lg disabled:opacity-75"
+                class="flex items-center gap-2 px-4 py-2 bg-red-600 hover:bg-red-700 text-white text-sm font-semibold rounded-lg disabled:opacity-75 min-h-[44px]"
               >
                 <AppSpinner v-if="signingOutAll" />
                 Sign out all devices
               </button>
-          </div>
+            </template>
+          </ConfirmBlock>
         </template>
       </section>
+
     </div>
   </div>
 </template>
@@ -108,20 +174,21 @@ import { useRouter } from 'vue-router'
 import { useAuthStore } from '../stores/auth.js'
 import * as api from '../api/client.js'
 import PasswordStrengthBar from '../components/auth/PasswordStrengthBar.vue'
+import TotpEnrollment from '../components/auth/TotpEnrollment.vue'
+import ConfirmBlock from '../components/ui/ConfirmBlock.vue'
 import AppSpinner from '../components/ui/AppSpinner.vue'
 
 const authStore = useAuthStore()
 const router = useRouter()
 
+// ── Change password ─────────────────────────────────────────────────────────
+
 const currentPassword = ref('')
 const newPassword = ref('')
 const changingPassword = ref(false)
 const passwordError = ref(null)
 const passwordSuccess = ref(null)
 
-const confirmSignOutAll = ref(false)
-const signingOutAll = ref(false)
-
 async function changePassword() {
   changingPassword.value = true
   passwordError.value = null
@@ -135,12 +202,51 @@ async function changePassword() {
     currentPassword.value = ''
     newPassword.value = ''
   } catch (e) {
-    passwordError.value = e.message
+    const msg = e.message || ''
+    if (msg.toLowerCase().includes('current') || msg.toLowerCase().includes('incorrect')) {
+      // Wrong current password — show inline below the field
+      passwordError.value = 'Current password is incorrect'
+    } else if (msg.toLowerCase().includes('breach')) {
+      // HIBP breach detected
+      passwordError.value = 'This password has appeared in a data breach. Choose a different password.'
+    } else {
+      passwordError.value = msg
+    }
   } finally {
     changingPassword.value = false
   }
 }
 
+// ── TOTP enrollment ─────────────────────────────────────────────────────────
+
+const confirmDisable2fa = ref(false)
+const totpError = ref(null)
+
+function onTotpEnrolled() {
+  // Update user totp_enabled flag in store
+  if (authStore.user) {
+    authStore.user.totp_enabled = true
+  }
+}
+
+async function disableTotp() {
+  totpError.value = null
+  try {
+    await api.totpDisable()
+    if (authStore.user) {
+      authStore.user.totp_enabled = false
+    }
+    confirmDisable2fa.value = false
+  } catch (e) {
+    totpError.value = e.message
+  }
+}
+
+// ── Sign out all devices ────────────────────────────────────────────────────
+
+const confirmSignOutAll = ref(false)
+const signingOutAll = ref(false)
+
 async function signOutAll() {
   signingOutAll.value = true
   try {