feat: 引入分层配置生命周期，支持变量引用和 JSON Schema 校验

- 新增 src/server/config/ 模块（types、issues、variables、normalizer、schema）
- 配置布局从 server.host/server.port 切换为 server.listen.host/server.listen.port
- 移除 HOST/PORT 隐式环境变量覆盖，改为 YAML 显式 ${KEY} 变量引用
- 支持 ${KEY}、${KEY|default}、${KEY|}、$${KEY} 变量语法
- 使用 @sinclair/typebox + ajv 实现运行时严格契约校验和 JSON Schema 导出
- 新增 scripts/generate-config-schema.ts 和 config.schema.json
- 新增 bun run schema / schema:check 命令，check 先执行 schema:check
- 更新 README.md 和 DEVELOPMENT.md 匹配新配置体系
- 新增变量解析、schema 校验和 schema 同步测试

package.json

@@ -10,7 +10,9 @@
     "build": "bun run scripts/build.ts",
     "lint": "eslint .",
     "format": "prettier . --write",
-    "check": "bun run typecheck && bun run lint && bun test",
+    "check": "bun run schema:check && bun run typecheck && bun run lint && bun test",
+    "schema": "bun run scripts/generate-config-schema.ts",
+    "schema:check": "bun run scripts/generate-config-schema.ts -- --check",
     "verify": "bun run check && bun run build",
     "test": "bun test",
     "clean": "bun run scripts/clean.ts",
@@ -49,7 +51,9 @@
     "vite": "^8.0.13"
   },
   "dependencies": {
+    "@sinclair/typebox": "^0.34.49",
     "@tanstack/react-query": "^5.100.10",
+    "ajv": "^8.20.0",
     "es-toolkit": "^1.46.1",
     "react": "^19.2.6",
     "react-dom": "^19.2.6",