dev-lifecycle

# Dev Lifecycle Coordinate the phase-specific AI DevKit skills instead of running phase details directly. Required phase skills: - `dev-worktree` for feature workspace setup and resume. - `dev-requirements` for phases 1-2: new requirement and requirements review. - `dev-design` for phase 3: design review. - `dev-planning` for phases 4 and 6: initial task planning and updates after implementation tasks. - `dev-implementation` for phases 5 and 7: execute plan and check implementation. - `dev-testing` for phase 8: write tests and verify coverage. - `dev-review` for phase 9: final code review. Supporting skills: - `memory` for reusable project knowledge during clarification. - `tdd` for implementation tasks. - `verify` before completing implementation, implementation checks, testing claims, and review readiness. - `task` for optional progress tracing when the task command is usable. ## Startup Validation At the beginning of every `dev-lifecycle` run: 1. Run `npx ai-devkit@latest skill list` to inspect currently installed project skills. 2. Confirm the listed skills include all required phase skills and supporting skills. 3. If any required skill is missing, run `npx ai-devkit@latest skill add --built-in` to install all AI DevKit built-in skills. Then rerun `npx ai-devkit@latest skill list`. 4. If installation fails or a required skill is still missing, stop and report the missing skill names and command output summary. Do not run a phase without its skill. 5. Run `npx ai-...