Pre-build KB indexes at startup, not on first query

backend/app.py

@@ -12,7 +12,7 @@ from pydantic import BaseModel
 
 from config import DOMAIN_CLIENTS, CLIENT_DOMAIN, DISPLAY_NAMES
 from grader import get_embedder, get_nli_model
-from pipeline import run
+from pipeline import run, _build_index
 
 log = logging.getLogger(__name__)
 logging.basicConfig(level=logging.INFO)
@@ -26,9 +26,11 @@ async def lifespan(app: FastAPI):
     if not hf_token:
         raise RuntimeError("HF_TOKEN not set")
     app.state.hf_client = InferenceClient(token=hf_token)
-    get_embedder()
+    embedder = get_embedder()
     get_nli_model()
-    log.info("Models pre-warmed. Ready.")
+    for domain in DOMAIN_CLIENTS:
+        _build_index(domain, embedder)
+    log.info("Models and KB indexes pre-warmed. Ready.")
     yield