Merge prgs/master into feat/issue-503-reviewer-active-worktree.
Preserve reviewer mutation workspace binding (#503) and fold in
master's review_pr task preflight checks via _verify_reviewer_mutation_workspace.
Reviewer mutation tools now resolve workspace from worktree_path,
GITEA_ACTIVE_WORKTREE, or the session reviewer lease before preflight
and branches-only validation. Preflight rejects metadata-only worktree_path
bindings that would mislead runtime_context while mutations still inspect
the MCP process root.
Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>