feat: 新增 jsc-matt 外掛，收錄 Matt Pocock 全套技能，指令為 /jsc-matt:*

- 改編自 mattpocock/skills 1.2.3（MIT），含 engineering 與 productivity 共 25 個技能
- 技能間的呼叫名稱一律加上 jsc-matt: 前綴
- marketplace 與 README 補上 jsc-matt

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

plugins/jsc-matt/.claude-plugin/plugin.json

@@ -0,0 +1,37 @@
+{
+  "name": "jsc-matt",
+  "version": "0.0.1",
+  "description": "Matt Pocock 的工程技能整套：grilling、spec/ticket 流程、TDD、code review、領域建模等。所有指令為 /jsc-matt:*",
+  "license": "MIT",
+  "author": {
+    "name": "JSC"
+  },
+  "keywords": ["engineering", "skills", "tdd", "code-review", "grilling", "domain-modeling"],
+  "skills": [
+    "./skills/engineering/ask-matt",
+    "./skills/engineering/diagnosing-bugs",
+    "./skills/engineering/grill-with-docs",
+    "./skills/engineering/triage",
+    "./skills/engineering/improve-codebase-architecture",
+    "./skills/engineering/setup-matt-pocock-skills",
+    "./skills/engineering/tdd",
+    "./skills/engineering/to-spec",
+    "./skills/engineering/to-tickets",
+    "./skills/engineering/wayfinder",
+    "./skills/engineering/implement",
+    "./skills/engineering/prototype",
+    "./skills/engineering/research",
+    "./skills/engineering/domain-modeling",
+    "./skills/engineering/codebase-design",
+    "./skills/engineering/code-review",
+    "./skills/engineering/resolving-merge-conflicts",
+    "./skills/engineering/wizard",
+    "./skills/productivity/grill-me",
+    "./skills/productivity/grilling",
+    "./skills/productivity/handoff",
+    "./skills/productivity/teach",
+    "./skills/productivity/to-questionnaire",
+    "./skills/productivity/wait-what",
+    "./skills/productivity/writing-for-agents"
+  ]
+}