Resume conflicted task PRs in the same worktree — agent before human escalation

Problem

When auto-rebase fails for a conflicted task PR, dispatch an agent to the existing worktree to resolve conflicts before escalating to a human operator.

Context

• auto_rebase_conflicted_pr_tasks() in scripts/task_manager_lib.py handles conflicted PRs today:
• Clean worktree + rebase succeeds → auto-rebased, no human needed
• Dirty worktree or rebase failure → immediate tier1 escalation to human (pr_conflict_dirty_branch / pr_conflict_needs_manual_rebase)
• The dirty-worktree and rebase-failure cases are the most common in practice. Often the conflict is resolvable by an agent that can read the merge markers and apply the right resolution — but today we skip straight to human escalation.
• The scripts/dispatch script already supports --path to reuse an existing worktree, so we can dispatch an agent to the same worktree with a conflict-resolution prompt.
• Key constraint: the agent dispatch must be optional and gated — not every caller wants to spawn a subprocess. The heartbeat and reconcile-pr-conflicts scripts should opt in explicitly.
• Relevant files:
• scripts/task_manager_lib.py — auto_rebase_conflicted_pr_tasks(), _note_attention()
• scripts/task-manager-reconcile-pr-conflicts — standalone operator command
• scripts/task-manager-heartbeat — main loop
• scripts/dispatch — agent dispatch infrastructure
• tests/scripts/test_task_manager_scripts.py — test suite

Possible Solutions

• Option 1: Keep current behavior — auto-rebase or immediate human escalation. Simple but leaves resolvable conflicts sitting until a human intervenes. Rejected.
• Option 2: Recommended Add a resume_conflicted_pr_via_agent() function that:
• Takes the list of tasks that auto_rebase_conflicted_pr_tasks() placed into "skipped" or "failed"
• For each, dispatches an agent to the existing worktree with a targeted conflict-resolution prompt (git fetch origin main && git rebase origin/main, resolve markers, commit, push)
• On agent success → record as "agent_resolved"
• On agent failure/timeout → escalate to human with pr_conflict_needs_human (tier1)
• Controlled by a --agent-resolve flag so callers opt in
• Option 3: Have the heartbeat auto-dispatch a full task-execute agent. Too heavyweight — we only need a narrow rebase-resolution prompt, not a full re-implementation. Rejected.

Plan

1. Write failing tests for resume_conflicted_pr_via_agent(): - Agent dispatch succeeds → task recorded as "agent_resolved", no human escalation - Agent dispatch fails → task escalated with pr_conflict_needs_human - Agent dispatch times out → same escalation - Tasks without worktree path → skipped
2. Implement resume_conflicted_pr_via_agent() in task_manager_lib.py: - Accept tasks + rebase results from auto_rebase_conflicted_pr_tasks() - Build a conflict-resolution prompt - Shell out to scripts/dispatch with --path <worktree> and a timeout - Collect results: agent_resolved, agent_failed, agent_skipped
3. Wire into scripts/task-manager-reconcile-pr-conflicts behind --agent-resolve flag.
4. Wire into heartbeat behind --agent-resolve flag (off by default).
5. Update task worksheet with implementation progress.

Implementation Progress

Files modified

• scripts/task_manager_lib.py — Added resume_conflicted_pr_via_agent() function with:
• Targeted conflict-resolution prompt (fetch, rebase, resolve markers, push)
• Dispatches agent to existing worktree via scripts/dispatch
• On success → agent_resolved, no human escalation
• On failure/timeout → pr_conflict_needs_human tier1 escalation
• Skips tasks without worktree path
• scripts/task-manager-reconcile-pr-conflicts — Added --agent-resolve and --agent-timeout flags. When --agent-resolve is passed, calls resume_conflicted_pr_via_agent() on tasks that auto-rebase skipped or failed. JSON and text output include agent results.
• tests/scripts/test_task_manager_scripts.py — 4 new tests:
• test_resume_conflicted_pr_via_agent_success — agent succeeds, no escalation
• test_resume_conflicted_pr_via_agent_failure_escalates — agent fails, human escalation
• test_resume_conflicted_pr_via_agent_timeout_escalates — agent times out, human escalation
• test_resume_conflicted_pr_via_agent_skips_no_worktree — no worktree, skipped

Key decisions

• Agent resolve is opt-in (--agent-resolve flag) — not enabled by default in heartbeat or reconcile
• The prompt is narrow: only resolve merge conflicts, no logic changes
• Escalation code is pr_conflict_needs_human (distinct from pr_conflict_needs_manual_rebase) to clearly indicate the agent path was tried first
• Heartbeat wiring deferred to follow-up — heartbeat doesn't currently call auto-rebase, so adding both rebase + agent-resolve would be a larger scope change

QA Exploration

• [x] QA exploration completed (or N/A for non-UI tasks)
• N/A: backend/orchestration task

Review Feedback

• [ ] Review cleared