_verify_role_mutation_workspace dropped org/repo, so anti-stomp resolved bare
remote=prgs to Timesheet and failed closed wrong_repo on Gitea-Tools. Forward
explicit org/repo for merger/reviewer lease acquire, adopt, review, merge, and
lease release. Add regression for merger acquire forwarding.
Fixes#718
Refs #723
gitea_acquire_merger_pr_lease previously continued when GET /pulls returned
an empty head SHA. Fail closed so exact-head scoping never proceeds with an
unresolvable live head. Add regression coverage for empty head payloads.
Fixes#718
Refs #723
Harden gitea_acquire_merger_pr_lease with required candidate_head, live-head
match, and fail-closed POST handling. Add capability-map aliases for reviewer
and merger lease acquire/adopt. Make unknown tasks return structured
unknown_task (no ValueError escape). Expand tests for roles, head scoping,
aliases, and unknown_task.
Closes#718. Addresses #723 resolver unknown_task and lease task mapping.
This implements the native merger lease acquisition tool to allow a merger session to acquire its own lease when a reviewer lease does not exist or has expired, unblocking #679 adoption.