feat: semantic search includes raw turns, deduplicate layers, fix recent turn ordering

- Layer 2 semantic search now queries both curated and raw types,
  closing the blind spot for turns past the 50-turn window pre-curation
- Layer 3 skips turns already returned by Layer 2 to avoid duplicate
  context and wasted token budget
- get_recent_turns uses Qdrant OrderBy for server-side timestamp sort
  with payload index; fallback to client-side sort if unavailable
- Bump version to 2.0.4

app/main.py

@@ -68,7 +68,7 @@ async def lifespan(app: FastAPI):
     await qdrant_service.close()
 
 
-app = FastAPI(title="Vera-AI", version="2.0.0", lifespan=lifespan)
+app = FastAPI(title="Vera-AI", version="2.0.4", lifespan=lifespan)
 
 
 @app.get("/")