feat(12-03): connection-ID routing, rename, session folder memory, thin views

- Route /cloud/:connectionId/:folderId replaces /cloud/:provider/:folderId
- api/cloud.js: getCloudFoldersByConnectionId + renameCloudConnection
- cloudConnections store: rename, selectConnection, setBrowseState, defaultDisplayName, session storage helpers
- CloudStorageView: thin — passes connectionRoots to StorageBrowser
- CloudFolderView: thin — uses connectionId param, never provider slug
- SettingsCloudTab: inline rename input for each active connection
- 27 tests pass: store, view, settings

frontend/src/components/settings/SettingsCloudTab.vue

@@ -60,8 +60,33 @@
 
               <!-- ACTIVE -->
               <template v-else-if="connectionFor(provider.key)?.status === 'ACTIVE'">
+                <!-- Rename display name -->
+                <template v-if="renamingId === connectionFor(provider.key)?.id">
+                  <input
+                    v-model="renameValue"
+                    class="border border-gray-300 rounded-lg px-2 py-1 text-sm w-40 focus:outline-none focus:ring-2 focus:ring-indigo-500"
+                    @keydown.enter="submitRename(connectionFor(provider.key)?.id)"
+                    @keydown.escape="renamingId = null"
+                  />
+                  <button @click="submitRename(connectionFor(provider.key)?.id)"
+                    class="text-sm px-2 py-1 text-indigo-600 hover:underline font-medium focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-indigo-500 focus-visible:ring-offset-1 rounded">
+                    Save
+                  </button>
+                  <button @click="renamingId = null"
+                    class="text-sm px-2 py-1 text-gray-500 hover:text-gray-700 focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-indigo-500 focus-visible:ring-offset-1 rounded">
+                    Cancel
+                  </button>
+                </template>
                 <button
-                  v-if="!OAUTH_PROVIDERS.has(provider.key) && confirmRemoveId !== connectionFor(provider.key)?.id"
+                  v-else-if="confirmRemoveId !== connectionFor(provider.key)?.id"
+                  @click="startRename(connectionFor(provider.key))"
+                  class="text-sm px-3 py-2 border border-gray-300 rounded-lg hover:bg-gray-50 active:bg-gray-100 text-gray-700 transition-colors focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-indigo-500 focus-visible:ring-offset-1"
+                  title="Rename connection"
+                >
+                  Rename
+                </button>
+                <button
+                  v-if="!OAUTH_PROVIDERS.has(provider.key) && confirmRemoveId !== connectionFor(provider.key)?.id && renamingId !== connectionFor(provider.key)?.id"
                   @click="handleEdit(provider)"
                   class="text-sm px-3 py-2 border border-gray-300 rounded-lg hover:bg-gray-50 active:bg-gray-100 text-gray-700 transition-colors focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-indigo-500 focus-visible:ring-offset-1"
                 >
@@ -216,6 +241,9 @@ const editingConnection = ref(null)
 const confirmRemoveId = ref(null)
 const showDisconnectAll = ref(false)
 const oauthError = ref('')
+const renamingId = ref(null)
+const renameValue = ref('')
+const renameError = ref('')
 
 onMounted(() => {
   store.fetchConnections()
@@ -297,4 +325,22 @@ async function handleDisconnectAll() {
 async function handleConnected() {
   await store.fetchConnections()
 }
+
+function startRename(connection) {
+  if (!connection) return
+  renamingId.value = connection.id
+  renameValue.value = connection.display_name || ''
+  renameError.value = ''
+}
+
+async function submitRename(id) {
+  if (!id) return
+  renameError.value = ''
+  try {
+    await store.rename(id, renameValue.value)
+    renamingId.value = null
+  } catch (e) {
+    renameError.value = e.message || 'Failed to rename connection'
+  }
+}
 </script>