Execute implementation plan tasks with TDD workflow, auto-commit, and phase gates. Use when user says "build it", "start building", "execute plan", "implement tasks", "ship it", or references a track ID. Do NOT use for planning (use /plan) or scaffolding (use /scaffold).

使用TDD工作流、自动提交和阶段门控执行实施计划任务。当用户说“构建它”“开始构建”“执行计划”“实现任务”“交付”或提及跟踪ID时使用。不要用于规划（请使用/plan）或搭建骨架（请使用/scaffold）。