[Deep-Sixed]

Summary

Adds .claude/hooks/session-start.sh and registers it in .claude/settings.json, so Claude Code on the web sessions can run the lint and test gates without manual setup.

The hook:

• installs pytest and ruff from pyproject.toml's dev dependency group. It reads the pins from there rather than repeating them, so it can't drift from the gate;
• installs uv 0.11.29, the version CI pins, and warms uv's cache so the uv run --with <pin> gate commands in verification.toml need no download mid-session;
• puts pip's scripts directory first on PATH for the session (via $CLAUDE_ENV_FILE). The web image preinstalls uv 0.8.17 and ruff 0.15.8 earlier on PATH, and without this they would shadow the pinned versions;
• does nothing outside the web (CLAUDE_CODE_REMOTE != true), and is safe to re-run.

It runs synchronously, so tools are ready before the session starts.

Validation

• The hook exits 0 on first run, on a re-run, and as a no-op outside the web. It takes about 5s once packages are cached.
• After the hook: uv 0.11.29, ruff 0.16.8, pytest 9.1.1 resolve first on PATH.
• uv run --with ruff==0.16.8 ruff check .: all checks passed.
• uv run --with pytest==9.1.1 python -m pytest -q tests/test_input_boundaries.py: 20 passed.
• Before this change, with pytest installed by hand: the full suite gave 417 passed and 1 skipped offline; the 3 network tests also passed.

🤖 Generated with Claude Code

https://claude.ai/code/session_01TjcFBXJq1YJterj78bETMh

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Generated by Claude Code