feat(chat): integrate chat project into monorepo with full app structure

- Restructure chat as apps/mobile, apps/web, apps/landing, backend
- Add NestJS backend for secure Azure OpenAI API calls
- Remove exposed API key from mobile app (security fix)
- Add shared chat-types package
- Create SvelteKit web app scaffold
- Create Astro landing page scaffold
- Update pnpm workspace configuration
- Add project-level CLAUDE.md documentation

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

chat/apps/mobile/scripts/update_models.sql

@@ -0,0 +1,29 @@
+-- Löschen der vorhandenen Modelle (optional)
+-- DELETE FROM models;
+
+-- Einfügen der neuen Modelle mit UUIDs
+INSERT INTO models (id, name, description, parameters)
+VALUES
+  (
+    '550e8400-e29b-41d4-a716-446655440000',
+    'GPT-O3-Mini',
+    'Azure OpenAI O3-Mini: Effizientes Modell für schnelle Antworten.',
+    '{"temperature": 0.7, "max_tokens": 800, "provider": "azure", "deployment": "gpt-o3-mini-se", "endpoint": "https://memoroseopenai.openai.azure.com", "api_version": "2024-12-01-preview"}'
+  ),
+  (
+    '550e8400-e29b-41d4-a716-446655440004',
+    'GPT-4o-Mini',
+    'Azure OpenAI GPT-4o-Mini: Kompaktes, leistungsstarkes KI-Modell.',
+    '{"temperature": 0.7, "max_tokens": 1000, "provider": "azure", "deployment": "gpt-4o-mini-se", "endpoint": "https://memoroseopenai.openai.azure.com", "api_version": "2024-12-01-preview"}'
+  ),
+  (
+    '550e8400-e29b-41d4-a716-446655440005',
+    'GPT-4o',
+    'Azure OpenAI GPT-4o: Das fortschrittlichste multimodale KI-Modell.',
+    '{"temperature": 0.7, "max_tokens": 1200, "provider": "azure", "deployment": "gpt-4o-se", "endpoint": "https://memoroseopenai.openai.azure.com", "api_version": "2024-12-01-preview"}'
+  )
+ON CONFLICT (id) 
+DO UPDATE SET 
+  name = EXCLUDED.name,
+  description = EXCLUDED.description,
+  parameters = EXCLUDED.parameters;