fix: 修复配额说明重复和undefined问题

- 在editStorageForm中初始化oss_storage_quota_value和oss_quota_unit
- 删除重复的旧配额说明块，保留新的当前配额设置显示

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

backend/node_modules/fs-constants/package.json

@@ -0,0 +1,19 @@
+{
+  "name": "fs-constants",
+  "version": "1.0.0",
+  "description": "Require constants across node and the browser",
+  "main": "index.js",
+  "browser": "browser.js",
+  "dependencies": {},
+  "devDependencies": {},
+  "repository": {
+    "type": "git",
+    "url": "https://github.com/mafintosh/fs-constants.git"
+  },
+  "author": "Mathias Buus (@mafintosh)",
+  "license": "MIT",
+  "bugs": {
+    "url": "https://github.com/mafintosh/fs-constants/issues"
+  },
+  "homepage": "https://github.com/mafintosh/fs-constants"
+}