fix(docker): ingest K8s corpus at build time for HF Spaces deploy

Dockerfile only baked the FastAPI store. Adds a second ingest RUN that
mirrors the existing one, so corpus=k8s requests work on the live
Space after push.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Dockerfile

@@ -17,8 +17,9 @@ RUN pip install --no-cache-dir .
 RUN python -c "from sentence_transformers import SentenceTransformer; SentenceTransformer('all-MiniLM-L6-v2')"
 RUN python -c "from sentence_transformers import CrossEncoder; CrossEncoder('cross-encoder/ms-marco-MiniLM-L-6-v2')"
 
-# Run ingestion at build time so the store is ready
+# Run ingestion at build time so both corpora stores are ready
 RUN python scripts/ingest.py --doc-dir data/tech_docs/ --store-path .cache/store
+RUN python scripts/ingest.py --doc-dir data/k8s_docs/ --store-path .cache/store_k8s
 
 # Give user 1000 ownership of build-time artifacts
 RUN chown -R user:user .cache/