chore: 移除packageManager字段并放宽pnpm版本限制

移除显式的packageManager字段，改为在engines中设置更宽松的pnpm版本范围(>=9 <=10.12)，提高兼容性

Author: feige996

package.json

@@ -3,7 +3,6 @@
   "type": "module",
   "version": "3.12.1",
   "unibest-version": "3.12.1",
-  "packageManager": "[email protected]",
   "description": "unibest - 最好的 uniapp 开发模板",
   "generate-time": "用户创建项目时生成",
   "author": {
@@ -22,7 +21,7 @@
   },
   "engines": {
     "node": ">=22",
-    "pnpm": "10.10.0"
+    "pnpm": ">=9 <=10.12"
   },
   "scripts": {
     "preinstall": "npx only-allow pnpm",