Sync coolify compose with main: remove voice-service, update rag/embedding

- Remove voice-service (removed in main branch)
- Remove voice_session_data volume
- Add OLLAMA_URL and OLLAMA_EMBED_MODEL to rag-service
- Update embedding-service default model to BAAI/bge-m3, memory 4G→8G
- Update health-aggregator CHECK_SERVICES (remove voice-service)
- Update .env.coolify.example accordingly

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.env.coolify.example

@@ -52,14 +52,13 @@ TRIAL_PERIOD_DAYS=14
 
 # --- Embedding Service ---
 EMBEDDING_BACKEND=local
-LOCAL_EMBEDDING_MODEL=sentence-transformers/all-MiniLM-L6-v2
+LOCAL_EMBEDDING_MODEL=BAAI/bge-m3
 LOCAL_RERANKER_MODEL=cross-encoder/ms-marco-MiniLM-L-6-v2
 PDF_EXTRACTION_BACKEND=pymupdf
 OPENAI_API_KEY=
 COHERE_API_KEY=
 LOG_LEVEL=INFO
 
-# --- Ollama (optional) ---
-OLLAMA_BASE_URL=
+# --- Ollama (optional, for RAG embeddings) ---
 OLLAMA_URL=
-OLLAMA_VOICE_MODEL=
+OLLAMA_EMBED_MODEL=bge-m3