fix: restore GET / root route (404 on HF Spaces health check)

app.py

@@ -173,6 +173,11 @@ def _generate(input_ids: torch.Tensor, req, streamer=None) -> torch.Tensor:
 # ---------------------------------------------------------------------------
 # Routes
 # ---------------------------------------------------------------------------
+@app.get("/")
+def root():
+    return {"status": "ok", "model": MODEL_ID, "ready": _model_ready}
+
+
 @app.get("/health")
 def health():
     return {