refactor: introduce appointment repository factory

[moreorover]

Summary

• Convert the appointment repository to a factory that accepts an optional Db/Tx once
• Add an appointment service factory for dependency injection in tests
• Update transaction appointment lookup to use the new repository object

Validation

• vp check
• vp run --filter @prive-admin-tanstack/application test
• vp run --filter @prive-admin-tanstack/api test
• vp run --filter @prive-admin-tanstack/db check-types

Note: root vp test currently picks up stale .worktrees/* and dist test files and fails outside this change scope.

[github-actions]

Dependency Review

✅ No vulnerabilities or license issues or OpenSSF Scorecard issues found.

Scanned Files

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