`full` ran every manual-stage hook in one pre-commit call, which takes
over 60 s in screen-locker and leetcode-guard. `step <hook-id>` runs one
manual hook on --all-files and records "<tree> <id>" in
$GIT_DIR/gate-steps (per-worktree); the step that completes the set
writes the stamp exactly as `write` does. Dirty trees and non-manual ids
are refused with exit 2. Hook ids come from scripts/gate_stamp_hooks.py
(PyYAML, /usr/bin/python3), which treats an absent default_stages as
"every stage", matching pre-commit, so the steps cover what `full` runs.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01PAhbNszs5JKdtnD4uBi3xp
