chore: update Docker configurations to streamline backend build and enhance E2E testing environment

surfsense_backend/Dockerfile

@@ -93,6 +93,9 @@ RUN printf '%s\n' \
     '    pass' \
     | python || true
 
+ARG EMBEDDING_MODEL=sentence-transformers/all-MiniLM-L6-v2
+RUN python -c "from chonkie import AutoEmbeddings; AutoEmbeddings.get_embeddings('${EMBEDDING_MODEL}')"
+
 # Install Playwright browsers (the playwright python package itself is in deps)
 RUN playwright install chromium --with-deps
 
@@ -104,6 +107,7 @@ RUN mkdir -p /shared_tmp
 ENV PYTHONPATH=/app
 ENV UVICORN_LOOP=asyncio
 ENV TMPDIR=/shared_tmp
+ENV PYTHONUNBUFFERED=1
 
 # Tune glibc malloc to return freed memory to the OS more aggressively.
 # Without these, Python's gc.collect() frees objects but the underlying

surfsense_backend/scripts/docker/entrypoint.e2e.sh

@@ -19,7 +19,8 @@ wait_for_db() {
     # depends_on/healthchecks already gate on db readiness, this is just
     # belt-and-suspenders so a slow first connection doesn't race migrations.
     for i in {1..60}; do
-        if python -c "from app.db import engine; import asyncio; asyncio.run(engine.dispose())" 2>/dev/null; then
+        echo "[e2e-entrypoint] db check attempt ${i}/60"
+        if python -c "from app.db import engine; import asyncio; asyncio.run(engine.dispose())"; then
             echo "[e2e-entrypoint] db reachable after ${i} attempts"
             return 0
         fi