fix: comments delete cascade

[Jayllyz]

Summary 📝

Deletion rules were missing in the comments table when the post or user is deleted.
Added more test case.

Which part of the repository is impacted ?

• API
• Client
• Admin
• Documentation
• CI/CD
• Other

[github-actions]

Coverage Report for API (./apps/api)

Status	Category	Percentage	Covered / Total
🟢	Lines	85.7% (🎯 70%)	5743 / 6701
🟢	Statements	85.7% (🎯 70%)	5743 / 6701
🟢	Functions	75% (🎯 40%)	9 / 12
🟢	Branches	42.22% (🎯 30%)	190 / 450

File Coverage

File	Stmts	% Branch	% Funcs	% Lines	Uncovered Lines
Changed Files
apps/api/src/handlers/blog.ts	88.09%	59.45%	100%	88.09%	46-47, 57-58, 66-67, 69, 84-85, 103-104, 146-147, 176-177, 192-193, 209-210, 220-221, 240-241, 262-263

Generated in workflow #359