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>

office-translator-landing-page/components/theme-provider.tsx

@@ -0,0 +1,11 @@
+'use client'
+
+import * as React from 'react'
+import {
+  ThemeProvider as NextThemesProvider,
+  type ThemeProviderProps,
+} from 'next-themes'
+
+export function ThemeProvider({ children, ...props }: ThemeProviderProps) {
+  return <NextThemesProvider {...props}>{children}</NextThemesProvider>
+}