refactor: 从 pnpm 切换到 npm

- 去掉 corepack/pnpm，Docker 构建不再卡在下载 pnpm
- Dockerfile 使用 npm ci + npm prune --omit=dev
- 删除 pnpm-lock.yaml，新增 package-lock.json

package.json

@@ -24,7 +24,6 @@
   ],
   "author": "",
   "license": "ISC",
-  "packageManager": "pnpm@10.25.0",
   "engines": {
     "node": ">=22.0.0"
   },
@@ -43,10 +42,5 @@
     "tsup": "^8.0.0",
     "typescript": "^5.7.0",
     "vitest": "^3.0.0"
-  },
-  "pnpm": {
-    "onlyBuiltDependencies": [
-      "esbuild"
-    ]
   }
 }