feat: add project-workflow skill — unified six-phase engineering life…

[zzx666-code]

…cycle orchestrator## Summary

Adds project-workflow, a meta-skill that orchestrates the entire agent-skills library
through a single, gate-controlled six-phase lifecycle (DEFINE → PLAN → BUILD → VERIFY
→ REVIEW → SHIP). Users can trigger it with a single sentence ("帮我写个项目",
"fix this bug", "add a feature"), and the agent automatically routes to the correct
sub-skills, enforces human checkpoints between phases, and produces verifiable evidence
at each gate.

Motivation

agent-skills has 20+ individual skills, but using them effectively requires knowing
which skill to invoke at which point. There was no single entry point that:

• Routes a vague request to the right phase (e.g., bug reports skip DEFINE/PLAN
  and go directly to VERIFY's Prove-It pattern)
• Enforces phase gates with explicit user confirmation before advancing
• Auto-activates the correct sub-skills based on context (e.g., frontend-ui-engineering
  when UI work is detected, security-and-hardening when auth is involved)
• Provides a shared code of conduct (three core operating principles + six bottom-line
  rules) that governs all sub-skill behavior

What's Included

• skills/project-workflow/SKILL.md — the full skill definition (276 lines).
  Covers: routing table by confidence level, six phases with evidence checklists,
  10 auto-activating sub-skills by context, bilingual Chinese/English triggers,
  comparison table vs plain agent-skills, anti-rationalization tables, and
  verification checklist.
• skills/project-workflow.zip — distribution package.

Structure of the Skill

Section	Content
Overview	Three core operating principles (Surface Assumptions, Manage Confusion Actively, Push Back When Warranted)
Six-Phase Lifecycle	DEFINE → PLAN → BUILD → VERIFY → REVIEW → SHIP, each with sub-skill routing, auto-activation table, and evidence checklist
Bottom-Line Principles	Six non-negotiable rules (Spec before code, Tests are proof, Thin vertical slices, etc.)
Usage	Chinese and English trigger examples
How It Differs	7-dimension comparison vs using agent-skills directly
Red Flags & Verification	Behavioral guardrails and exit criteria

How to Test

Load the skill into any agent that supports Markdown skill discovery. Trigger it with:

• "帮我写个项目" — should route to DEFINE phase
• "Fix this bug: the login page crashes on empty password" — should route to VERIFY
• "Add a feature: task list filtering" — should route to DEFINE, write a spec

[addyosmani]

Going to close this one. A "unified six-phase lifecycle orchestrator" is what using-agent-skills already is, so this duplicates the meta-skill rather than adding a capability, and the branch has gone stale on top of that. The instinct to give people a single front door is right, it just happens to be the front door we already have. Appreciate the effort, and please keep contributing.