Local launch and managed startup now start the incoming-key owner for
sessions installed with keyboard-inject, using one input-helper
Supervisor retained for the reader lifetime. Delivery rechecks lock,
XTerm handoff and internal reader UI in addition to lease, grant and
deadline. build-cthulhu.sh and both Arch packages build and install
cthulhu-input-helper; a missing helper leaves keyboard input
unavailable without affecting startup.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>