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/strnum/test.js

@@ -0,0 +1,9 @@
+import toNumber from "./strnum.js";
+
+describe("Should convert all the valid numeric strings to number", () => {
+  it("should return undefined, null, empty string, or non-numeric as it is", () => {
+      // expect(toNumber("+ 90")).toEqual("+ 90");
+      // expect(toNumber("- 90")).toEqual("- 90");
+      expect(toNumber("-10E2")).toEqual(100);
+  });
+});