docs(skill): 覆盖率阶段 1 样板 —— req / ai-proj 的 evals 与四段式文档

- skills-req/req-plugin/skills/evals/evals.json（3 条：正常/边界/失败恢复）
- docs/skills/req.md（What/When/Common questions/It's working if）
- skills-core/ai-proj-plugin/skills/evals/evals.json
- docs/skills/ai-proj.md
- coverage: 40 -> 38

catalog.json

@@ -2,10 +2,9 @@
   "repo": "ai-proj-helper",
   "coverage": {
     "required": 40,
-    "with_evals": 0,
-    "with_docs": 0,
+    "with_evals": 2,
+    "with_docs": 2,
     "missing_evals": [
-      "ai-proj",
       "pm-ask",
       "pm-risk",
       "agent-browser",
@@ -37,7 +36,6 @@
       "req-design",
       "req-dev",
       "req-lookback",
-      "req",
       "req-prd",
       "req-prototype",
       "req-research",
@@ -47,7 +45,6 @@
       "req-workflow"
     ],
     "missing_docs": [
-      "ai-proj",
       "pm-ask",
       "pm-risk",
       "agent-browser",
@@ -79,7 +76,6 @@
       "req-design",
       "req-dev",
       "req-lookback",
-      "req",
       "req-prd",
       "req-prototype",
       "req-research",
@@ -89,7 +85,7 @@
       "req-workflow"
     ]
   },
-  "generated_at": "2026-10-31T21:04:04Z",
+  "generated_at": "2026-10-31T21:07:49Z",
   "total": 61,
   "counts": {
     "promoted/user-invoked": 18,
@@ -174,8 +170,8 @@
       "description_len": 77,
       "path": "skills-core/ai-proj-plugin/skills/SKILL.md",
       "digest": "77ce4d2eb10e1d29",
-      "has_evals": false,
-      "has_docs": false
+      "has_evals": true,
+      "has_docs": true
     },
     {
       "name": "pm-ask",
@@ -785,8 +781,8 @@
       "description_len": 90,
       "path": "skills-req/req-plugin/skills/SKILL.md",
       "digest": "193cf871b73faff1",
-      "has_evals": false,
-      "has_docs": false
+      "has_evals": true,
+      "has_docs": true
     },
     {
       "name": "req-prd",