feat: 品牌替换 + 启动优化 + AGENTS.md 模板定制

- 品牌替换：OpenCode/opencode → AirCoding/aircoding（16+ 文件）
- Logo ASCII art：修复 left/right 行数不匹配导致的启动崩溃
- 启动诊断：添加 OPENCODE_PRINT_TIMING 计时探针
- dev 模式默认 --pure 跳过外部插件加载
- AGENTS.md 模板：追加 AirCoding 多 Agent 专项段落
- architect prompt + plugin：强化 AGENTS.md 产出验证

github/package.json

@@ -0,0 +1,20 @@
+{
+  "name": "github",
+  "module": "index.ts",
+  "type": "module",
+  "private": true,
+  "license": "MIT",
+  "devDependencies": {
+    "@types/bun": "catalog:"
+  },
+  "peerDependencies": {
+    "typescript": "^5"
+  },
+  "dependencies": {
+    "@actions/core": "1.11.1",
+    "@actions/github": "6.0.1",
+    "@octokit/graphql": "9.0.1",
+    "@octokit/rest": "catalog:",
+    "@opencode-ai/sdk": "workspace:*"
+  }
+}