refactor: 削除イベントを発行するようにした

[laminne]

close #1836

What does this PR do?

• setDeletedAtをdeprecatedにし、deleteメソッドに処理を移植
• setDeletedAtのないモデルはdeleteメソッドを新設

Additional information

• 感想: イベントが発行されるかのテスト、毎回書くと面倒なのでもう少し良くしたい気もする(アイデアはない)

[codecov]

Codecov Report

❌ Patch coverage is 70.00000% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 47.65%. Comparing base (50d7dc2) to head (faac3b1).

Files with missing lines	Patch %	Lines
pkg/accounts/model/follow.ts	33.33%	2 Missing ⚠️
pkg/notes/model/directNote.ts	71.42%	2 Missing ⚠️
pkg/notes/model/note.ts	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1840      +/-   ##
==========================================
+ Coverage   47.36%   47.65%   +0.28%     
==========================================
  Files         171      171              
  Lines        5882     5901      +19     
  Branches      886      891       +5     
==========================================
+ Hits         2786     2812      +26     
+ Misses       3096     3089       -7     

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