feat: automated Qdrant sync with Mistral embeddings + Kabelhandbuch ingestion

- Switch embedding API from OpenRouter to Mistral mistral-embed (1024-dim, EU/DSGVO)
- Add afterChange/afterDelete hooks to Posts.ts and Pages.ts for live sync
- Integrate kabelhandbuch.txt parsing into /api/sync-qdrant boot route
- Add .gitignore entries for kabelhandbuch.txt

src/scripts/ingest-pdf.ts

@@ -1,6 +1,7 @@
 import fs from 'fs';
 import path from 'path';
 import crypto from 'crypto';
+import 'dotenv/config';
 
 // Override Qdrant URL for local script execution outside docker
 process.env.QDRANT_URL = process.env.QDRANT_URL || 'http://localhost:6333';