fix: configure stdio-based MCP servers (penpot, imap)

- Set penpot-mcp restart: "no" for on-demand execution
- Create custom Dockerfile for imap-mcp with python module entrypoint
- Fix IMAP_HOST environment variable naming (was IMAP_SERVER)
- Update .env and docker-compose.yml for IMAP_HOST
- Remove command overrides from imap-mcp and penpot-mcp
- Verify penpot-mcp and imap-mcp work correctly

dockerfiles/imap-mcp/Dockerfile

@@ -0,0 +1,24 @@
+FROM python:3.12-slim
+
+# Install uv for faster package management
+COPY --from=ghcr.io/astral-sh/uv:latest /uv /uvx /bin/
+
+WORKDIR /app
+
+# Copy dependency files
+COPY pyproject.toml ./
+
+# Install dependencies
+RUN uv sync --no-dev --no-install-project --no-cache
+
+# Copy source code
+COPY . .
+
+# Install the project
+RUN uv sync --no-dev --no-editable --no-cache
+
+# Set up environment
+ENV PYTHONUNBUFFERED=1
+ENV PATH=/app/.venv/bin:$PATH
+
+ENTRYPOINT ["python", "-m", "imap_mcp.server"]