- Extend the POSIX launcher guard to also require `[ -r ]`, not just `-f`/`-x`,
so an executable-but-unreadable managed script still drains stdin instead of
erroring or silently misbehaving.
- Add a verifier case (`verifyClaudeDevinSkip`) that spins up a local HTTP
server and confirms the Claude hook never forwards a request that Devin
already imported, catching accidental double-forwarding.
- Update installer-utils tests and stdin-lifecycle docs to match the new
readable-file guard and the added verification case.
Generated agent hook scripts and missing-script launchers could exit
successfully before consuming the payload written to their stdin,
leaving the writer with a broken pipe (EPIPE/ERROR_BROKEN_PIPE) once
the reader closed early. Capture stdin (or drain it via a shared
epilogue/fast-path guard) before any whole-script success exit across
all POSIX, batch, PowerShell, and Git Bash launcher variants, and add
a cross-agent lifecycle test suite plus a live Electron verification
script to guard the contract going forward.
Jinjing