Add git to Dockerfile and httpx dependency

- Install git in Docker image for pip to clone git dependencies
- Add httpx package required by auth_service

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Dockerfile

@@ -2,6 +2,9 @@ FROM python:3.11-slim
 
 WORKDIR /app
 
+# Install git for pip to clone dependencies
+RUN apt-get update && apt-get install -y --no-install-recommends git && rm -rf /var/lib/apt/lists/*
+
 # Install dependencies
 COPY requirements.txt .
 RUN pip install --no-cache-dir -r requirements.txt