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/hero-section.tsx

@@ -0,0 +1,35 @@
+import { FileSpreadsheet, FileText, Presentation } from "lucide-react"
+
+export function HeroSection() {
+  return (
+    <section className="flex flex-col items-center gap-6 px-6 pt-16 pb-8 text-center md:pt-24 md:pb-12">
+      <div className="flex items-center gap-2 rounded-full border border-border bg-card px-4 py-1.5 text-xs font-medium text-muted-foreground shadow-sm">
+        <span className="inline-block size-1.5 rounded-full bg-success" />
+        Now with Pro LLM Engine
+      </div>
+
+      <h1 className="max-w-2xl text-balance text-4xl font-bold leading-tight tracking-tight text-foreground md:text-5xl lg:text-6xl">
+        Translate Office Documents. Keep the Format Perfect.
+      </h1>
+
+      <p className="max-w-xl text-pretty text-base leading-relaxed text-muted-foreground md:text-lg">
+        Upload your Excel, Word, or PowerPoint files and get accurate translations with zero formatting loss.
+      </p>
+
+      <div className="flex items-center gap-6 pt-2">
+        <div className="flex items-center gap-2 text-sm text-muted-foreground">
+          <FileSpreadsheet className="size-4" />
+          <span>.xlsx</span>
+        </div>
+        <div className="flex items-center gap-2 text-sm text-muted-foreground">
+          <FileText className="size-4" />
+          <span>.docx</span>
+        </div>
+        <div className="flex items-center gap-2 text-sm text-muted-foreground">
+          <Presentation className="size-4" />
+          <span>.pptx</span>
+        </div>
+      </div>
+    </section>
+  )
+}