fix: 收敛 2925 邮箱修复范围

- 回退非必要的 2925 行为改动，仅保留已验证有效的修复
- 保留 bounce 转发地址解析、中文日期解析与邮箱页复用时的 ready 恢复
- 同步最小化测试断言，保持当前代码与测试一致

background/verification-flow.js

@@ -214,7 +214,8 @@
 
     function getVerificationPollPayload(step, state, overrides = {}) {
       const is2925Provider = state?.mailProvider === '2925';
-      const mail2925MatchTargetEmail = is2925Provider;
+      const mail2925MatchTargetEmail = is2925Provider
+        && String(state?.mail2925Mode || '').trim().toLowerCase() === 'receive';
       if (step === 4) {
         return {
           filterAfterTimestamp: is2925Provider ? 0 : getHotmailVerificationRequestTimestamp(4, state),