feat(authorization): Policy インタフェースの定義，AccountPolicy の実装

[laminne]

close #1410

What does this PR do?

• feat: アクセス制御/権限に関するドキュメントを追加する specification#10 で定義した Policy クラス群のインタフェースを定義
• Accountモジュールの Policy クラス実装，AccountPolicy を実装
  • interfaceはクラスの非staticメソッドの形しか定義できないので，Policy インタフェースを満たすオブジェクトとして実装しました

Additional information

• 同時に Account モデルの状態をモデル外で判別するのではなく，モデルで判定を行えるよう新しいメソッドを追加しています
  • getFrozen(): AccountFrozenなどはDeprecatedにしました

[codecov]

Codecov Report

❌ Patch coverage is 9.30233% with 78 lines in your changes missing coverage. Please review.
✅ Project coverage is 41.71%. Comparing base (bfa5875) to head (7ba182d).
⚠️ Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
pkg/accounts/policy/accountPolicy.ts	0.00%	69 Missing ⚠️
pkg/accounts/model/account.ts	47.05%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1435      +/-   ##
==========================================
- Coverage   42.28%   41.71%   -0.58%     
==========================================
  Files         142      143       +1     
  Lines        5326     5399      +73     
  Branches      883      910      +27     
==========================================
  Hits         2252     2252              
- Misses       3074     3147      +73     

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