[QA] ✅ VERIFIED - All acceptance criteria met. 578 tests pass (including 39 new planning tests). Code quality is excellent with proper documentation, type hints, and error handling. No security issues identified. Implementation successfully adds --plan flag that executes issues in dependency order, respects blocked-by relationships, detects circular dependencies, and tracks timing for each issue. Ready for production use. See /tmp/qa-PLOW-33.md for full verification report.

Implemented planning mode for dependency-aware issue execution. ## Changes Made ### New Files - src/trckr_plow/planning.py: Planning module with DependencyGraph, IssueTiming, PlanningStats, load_issues_from_trckr(), and build_dependency_graph() - tests/test_planning.py: 39 unit tests for the planning module ### Modified Files - src/trckr_plow/cli.py: Added --plan flag to run command - src/trckr_plow/workflow_v2.py: Added plan_mode parameter and run_plan() method - tests/test_cli.py: Added tests for --plan flag ## Features - trckr-plow run --plan --use-config executes issues in dependency order - Respects blocked-by relationships (won't start blocked issues) - Falls back to priority order when no dependencies exist - Detects and reports circular dependencies - Tracks timing for each issue with summary at end ## Test Results - 574 tests pass - Lint passes with ruff