fix(ios): resolve native asset registration issues in New Architecture

[hallauman]

This commit fixes an issue where native ad assets could not be found via their react tags when the New Architecture (Fabric) was enabled.

• Added a recursive findViewByTag:inView: helper method to navigate the view hierarchy.
• Updated registerAsset:reactTag: to use the new lookup logic in New Architecture.
• The lookup now searches within both the _nativeAdView and the component itself.

Description

Related issues

Release Summary

Checklist

• I read the Contributor Guide
  and followed the process outlined there for submitting PRs.
  • Yes
• My change supports the following platforms;
  • Android
  • iOS
• My change includes tests;
  • e2e tests added or updated in __tests__e2e__
  • jest tests added or updated in __tests__
• I have updated TypeScript types that are affected by my change.
• This is a breaking change;
  • Yes
  • No

Test Plan

---

Think react-native-google-mobile-ads is great? Please consider supporting the project with any of the below:

• 👉 Star this repo on GitHub ⭐️
• 👉 Follow Invertase on Twitter

[docs-page]

To view this pull requests documentation preview, visit the following URL:

docs.page/invertase/react-native-google-mobile-ads~843

Documentation is deployed and generated using docs.page.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.

---

이명규 seems not to be a GitHub user. You need a GitHub account to be able to sign the CLA. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 36.02%. Comparing base (a34c7ba) to head (f2e7988).
⚠️ Report is 230 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #843      +/-   ##
==========================================
- Coverage   43.72%   36.02%   -7.69%     
==========================================
  Files          30       36       +6     
  Lines         549      658     +109     
  Branches      151      167      +16     
==========================================
- Hits          240      237       -3     
- Misses        309      421     +112     

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.