[routes-d] Switch contacts DELETE to soft-delete with deletedAt

[davedumto]

Summary

Make contact deletion a soft delete (under /api/routes-d/contacts/[id]).

Requirements

• Add a deletedAt column and filter it from reads
• Preserve referential integrity for linked invoices
• Add or update unit tests covering this change
• Keep behavior consistent with existing routes-d conventions

Acceptance criteria

• Change scoped to the named endpoint/area
• Behavior consistent with existing routes conventions
• Tests added or updated and passing in CI

[razeprasine]

@razeprasine has applied to work on this issue as part of the Stellar Wave Program's 5th wave.

Hi maintainer, i will love to resolve this issue

ℹ️ Repo Maintainers: To accept this application, review their application or assign @razeprasine to this issue.

[drips-wave]

Congratulations, @razeprasine! 🎉 Your application was accepted by the repo's maintainers, and the issue is due on June 2, 2026.

🧑‍💻 @razeprasine: Please resolve the issue such that the repo's maintainers have enough time to review your contribution before the due date. You'll earn Points for completing the issue on-time, which will make you eligible for a share of the Stellar Wave Program's reward pool.

Warning

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