faircode-mcp fails with a raw ModuleNotFoundError traceback when the mcp extra is not installed #995

Where: faircode/mcp_server.py build_server() (the from mcp.server.mcpserver import MCPServer import, line 524) and main(), pyproject.toml ([project.scripts]), tests/test_mcp_server.py.

Current gap: the module docstring says the server needs pip install faircode[mcp], but running the console script without the extra ends in a Python traceback ending ModuleNotFoundError: No module named 'mcp'. Every other optional extra (excel, proxy, benchmark) turns its missing import into a one-line message that names the extra. #987 now starts the server over stdio, but only with the extra present.

Repro:

$ python3 -m venv /tmp/v && /tmp/v/bin/pip install -e . && /tmp/v/bin/faircode-mcp
Traceback (most recent call last): ...
ModuleNotFoundError: No module named 'mcp'

Suggested approach: catch the ImportError in main(), print faircode-mcp needs the optional 'mcp' extra: pip install faircode[mcp] to stderr and exit 2, and test it by running the entry point in a subprocess with mcp blocked (python -c "import sys; sys.modules['mcp'] = None; ...").