fix: count initial HeroSMS free reuse success

- 合并 PR #209 的核心改动：HeroSMS 白嫖复用号码首次成功后立即计入 successfulUses/maxUses，并补充对应回归断言。
- 本地补充修复：无，本地审查未发现需要额外修补的冲突或逻辑问题。
- 影响范围：background/phone-verification-flow.js、tests/phone-verification-flow.test.js

tests/phone-verification-flow.test.js

@@ -4227,6 +4227,8 @@ test('phone verification helper preserves newly saved free-reuse activation afte
   assert.equal(currentState.freeReusablePhoneActivation.activationId, 'new-free-success');
   assert.equal(currentState.freeReusablePhoneActivation.phoneNumber, '66950007777');
   assert.equal(currentState.freeReusablePhoneActivation.source, 'free-manual-reuse');
+  assert.equal(currentState.freeReusablePhoneActivation.successfulUses, 1);
+  assert.equal(currentState.freeReusablePhoneActivation.maxUses, 3);
   assert.equal(
     requests.some((requestUrl) => (
       requestUrl.searchParams.get('action') === 'setStatus'