security: patch orjson DoS and harden container/frontend (#852)

Author: RinZ27

Dockerfile

@@ -26,4 +26,7 @@ RUN --mount=type=cache,target=/root/.cache/uv \
 EXPOSE 8000
 
 # Run the application.
+RUN useradd -m appuser
+USER appuser
+
 CMD ["uv", "run", "python", "server.py", "--host", "0.0.0.0", "--port", "8000"]

pyproject.toml

@@ -50,6 +50,7 @@ dependencies = [
     "psycopg[binary]>=3.2.9",
     "qdrant-client>=1.15.1",
     "langchain-qdrant>=0.2.0",
+    "orjson>=3.11.5",
 ]
 
 [project.optional-dependencies]