[QA PASSED] Comprehensive verification completed. Implementation verified at workflow_v2.py:1233-1365 (133 lines). All 22 new tests pass covering all 4 required transition points (after_triage, after_worker, after_qa, after_check_issue_status). Full regression test suite passes (401/401 tests). No issues found. Method correctly: (1) gets transitions from config, (2) formats messages with/without issue_id, (3) executes all action types, (4) returns proper (action, step) tuples, (5) raises dynamic exceptions. Code quality excellent. Merged to master successfully. Detailed QA report: /tmp/qa-PLOW-5.md

Implementation Complete: Added _handle_status_transition() method (workflow_v2.py:1233-1365). Method handles config-driven status transitions for all 4 transition points (after_triage, after_worker, after_qa, after_check_issue_status). Returns (action, step) tuples. 22 tests added. All 401 tests pass, linting passes. Merged to master.