feat: production deployment - full update with providers, admin, glossaries, pricing, tests

Major changes across backend, frontend, infrastructure:
- Provider system with model selection (Google, DeepL, OpenAI, Ollama, Google Cloud)
- Admin panel: user management, pricing, settings
- Glossary system with CSV import/export
- Subscription and tier quota management
- Security hardening (rate limiting, API key auth, path traversal fixes)
- Docker compose for dev, prod, and IONOS deployment
- Alembic migrations for new tables
- Frontend: dashboard, pricing page, landing page, i18n (en/fr)
- Test suite and verification scripts

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/package.json

@@ -28,17 +28,21 @@
     "@radix-ui/react-tabs": "^1.1.13",
     "@radix-ui/react-toast": "^1.2.15",
     "@radix-ui/react-tooltip": "^1.2.8",
+    "@react-oauth/google": "^0.13.5",
     "@tanstack/react-query": "^5.90.21",
+    "agentation-mcp": "^1.2.0",
     "class-variance-authority": "^0.7.1",
     "clsx": "^2.1.1",
     "framer-motion": "^12.23.24",
     "lucide-react": "^0.555.0",
     "next": "16.0.6",
     "next-intl": "^4.8.3",
+    "next-themes": "^0.4.6",
     "react": "19.2.0",
     "react-dom": "19.2.0",
     "react-dropzone": "^14.3.8",
     "tailwind-merge": "^3.4.0",
+    "xlsx": "^0.18.5",
     "zustand": "^5.0.9"
   },
   "devDependencies": {
@@ -49,6 +53,7 @@
     "@types/react": "^19",
     "@types/react-dom": "^19",
     "@vitejs/plugin-react": "^5.1.4",
+    "agentation": "^3.0.2",
     "eslint": "^9",
     "eslint-config-next": "16.0.6",
     "jsdom": "^28.1.0",