fix(frontend): mCaptchaが動作しない問題を修正

[kakkokari-gtyih]

What

mCaptchaとのやり取りをより低レベルなライブラリを使用するようにし、描画自体（iframeを出すの自体）はVueで行うように

Why

Fix #17107

Additional info (optional)

demo.mcaptcha.org (v0.1.0-b215a411) で動作することを確認

Checklist

• Read the contribution guide
• Test working in a local environment
• (If needed) Add story of storybook
• (If needed) Update CHANGELOG.md
• (If possible) Add tests

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 13.84%. Comparing base (cdb958c) to head (d7a40d6).
⚠️ Report is 53 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop   #17127      +/-   ##
===========================================
- Coverage    14.03%   13.84%   -0.19%     
===========================================
  Files          238      241       +3     
  Lines        11296    11663     +367     
  Branches      3736     3945     +209     
===========================================
+ Hits          1585     1615      +30     
- Misses        7586     7883     +297     
- Partials      2125     2165      +40     

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[syuilo]

🙏🙏