subagent_gate.py derived package name dynamically from CWD (mirrors edit_gate), replacing 3 hardcoded src/aipass/ paths. Branch detection + cross-branch protection now work for external projects (src/<package>/<branch>); previously silently no-opped. 5 new external-project tests (258 pass), seedgo 100%. Closes #605 Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>