refactor: 确立独立子工程架构 (backend, admin, mpuniapp) 并同步更新 AGENTS.md 规范

backend/.gitignore

@@ -0,0 +1,21 @@
+logs/
+cache/
+npm-debug.log
+yarn-error.log
+node_modules/
+package-lock.json
+yarn.lock
+coverage/
+dist/
+.idea/
+run/
+build/
+.DS_Store
+launch.json
+*.sw*
+*.un~
+.tsbuildinfo
+.tsbuildinfo.*
+data/*
+pnpm-lock.yaml
+public/uploads/*