continue_merge and the parent/children unit-merge drain (PlanningMergeOrchestrator)
re-run the post-merge verify gate but never forwarded their IProgress token into it,
so a slow verify command on either path went silent past Claude Code's 300s MCP
idle-abort even though D1-D3 already fixed this for merge_task/review_task's
childless path. list_worktrees also gets elapsed-time progress: many tracked
worktrees means many concurrent git subprocess spawns.
Worker CLAUDE.md's existing progress rule now points at ProgressReporter as the
one implementation instead of a fresh polling loop.