T07a: frontend core SPA — shell + auth + routing + i18n + UI library + a11y

- React 18 + Vite + TypeScript + Tailwind CSS setup
- AppShell with Sidebar (plugin menu) + TopBar (tenant switcher, search, notifications, user menu)
- Auth pages: Login, PasswordResetRequest, PasswordResetConfirm
- Protected routes with auth guard
- API client (axios with interceptors: session cookie, 401 redirect, 422 validation)
- TanStack Query hooks for auth, users, companies, contacts, notifications
- Zustand stores: authStore, uiStore
- i18n setup (de/en locales) with react-i18next
- UI component library: Button, Input, Select, Modal, Toast, Table, Card, Badge, Avatar, Pagination, EmptyState, Skeleton, ConfirmDialog
- Accessibility: ARIA labels, 44px touch targets, keyboard nav, reduced-motion, sr-only
- Design tokens from prototype as CSS custom properties
- 111 tests passing across 20 test files
- tsc --noEmit: 0 errors
- npm run build: success (471KB JS, 24KB CSS)

frontend/package.json

@@ -0,0 +1,46 @@
+{
+  "name": "leocrm-frontend",
+  "private": true,
+  "version": "1.0.0",
+  "type": "module",
+  "scripts": {
+    "dev": "vite",
+    "build": "tsc --noEmit && vite build",
+    "preview": "vite preview",
+    "test": "vitest run src/__tests__/ --reporter=verbose",
+    "test:coverage": "vitest run src/__tests__/ --coverage",
+    "typecheck": "tsc --noEmit"
+  },
+  "dependencies": {
+    "react": "^18.3.1",
+    "react-dom": "^18.3.1",
+    "react-router-dom": "^6.26.0",
+    "@tanstack/react-query": "^5.56.0",
+    "zustand": "^4.5.5",
+    "react-i18next": "^15.0.0",
+    "i18next": "^23.14.0",
+    "i18next-browser-languagedetector": "^8.0.0",
+    "react-hook-form": "^7.53.0",
+    "zod": "^3.23.8",
+    "@hookform/resolvers": "^3.9.0",
+    "axios": "^1.7.7",
+    "clsx": "^2.1.1"
+  },
+  "devDependencies": {
+    "@types/react": "^18.3.8",
+    "@types/react-dom": "^18.3.0",
+    "@vitejs/plugin-react": "^4.3.1",
+    "typescript": "^5.6.0",
+    "vite": "^5.4.0",
+    "vitest": "^2.1.0",
+    "@vitest/coverage-v8": "^2.1.0",
+    "jsdom": "^25.0.0",
+    "@testing-library/react": "^16.0.1",
+    "@testing-library/jest-dom": "^6.5.0",
+    "@testing-library/user-event": "^14.5.2",
+    "tailwindcss": "^3.4.13",
+    "postcss": "^8.4.47",
+    "autoprefixer": "^10.4.20",
+    "identity-obj-proxy": "^3.0.0"
+  }
+}