chore(08-08): PERF-01 packages + Vite 6 upgrade + pin requirements.txt

- Upgraded vite 5.4.21 → 6.4.3 (fixes CVE-2026-39363, CVE-2026-39364)
- Upgraded @vitejs/plugin-vue 5.2.4 → 6.0.7 (Vite 6 peer dep)
- Installed @vueuse/core@14.3.0, @vueuse/integrations@14.3.0,
  sortablejs@1.15.7, @tailwindcss/forms@0.5.11,
  rollup-plugin-visualizer@7.0.1, @types/sortablejs@1.15.9
- Wired @tailwindcss/forms plugin in tailwind.config.js (VISUAL-02 ready)
- Pinned backend/requirements.txt to exact == versions per D-17 (32 packages)
- Frontend: 136/136 tests pass on Vite 6; 0 npm audit vulnerabilities
- Backend: 408 passed, 4 skipped, 7 xfailed (baseline 405+1)
- Phase 8 complete (8/8 plans)

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/package.json

@@ -9,19 +9,25 @@
     "test": "vitest run"
   },
   "dependencies": {
+    "@tailwindcss/forms": "^0.5.11",
+    "@vueuse/core": "^14.3.0",
+    "@vueuse/integrations": "^14.3.0",
     "pinia": "^2.1.0",
     "qrcode": "^1.5.4",
-    "vue": "^3.4.0",
+    "sortablejs": "^1.15.7",
+    "vue": "^3.5.38",
     "vue-router": "^4.3.0"
   },
   "devDependencies": {
-    "@vitejs/plugin-vue": "^5.0.0",
+    "@types/sortablejs": "^1.15.9",
+    "@vitejs/plugin-vue": "^6.0.7",
     "@vue/test-utils": "^2.4.10",
     "autoprefixer": "^10.4.0",
     "happy-dom": "^20.9.0",
     "postcss": "^8.4.0",
+    "rollup-plugin-visualizer": "^7.0.1",
     "tailwindcss": "^3.4.0",
-    "vite": "^5.2.0",
+    "vite": "^6.4.3",
     "vitest": "^4.1.7"
   }
 }

frontend/tailwind.config.js

@@ -1,8 +1,9 @@
 /** @type {import('tailwindcss').Config} */
+import forms from '@tailwindcss/forms'
 export default {
   content: ['./index.html', './src/**/*.{vue,js}'],
   theme: {
     extend: {},
   },
-  plugins: [],
+  plugins: [forms],
 }