Unit Tests for NotificationsService

[Josue19-08]

🔖 Title

Unit Tests for NotificationsService

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📄 Description

Write comprehensive unit tests for the NotificationsService covering notification listing, filtering, and marking as read. Mock database operations. This issue can be completed independently once issues #60 and #61 are implemented.

Related to: Meta-issue #67

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✅ Tasks to complete

• Test listing notifications for a user
• Test filtering notifications by read/unread status
• Test filtering notifications by type
• Test pagination of notification list
• Test unread count calculation
• Test marking individual notification as read
• Test marking all notifications as read
• Test validation of notification ownership
• Test handling of non-existent notification IDs
• Test handling of empty notification lists
• Mock database queries
• Achieve 80%+ coverage for NotificationsService

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📚 Documentation/context for AI

(This link never should removed)
https://github.com/TrustUp-app/TrustUp-API/tree/main/docs

Relevant documentation:

• https://github.com/TrustUp-app/TrustUp-API/blob/main/docs/development/testing-structure.md
• https://github.com/TrustUp-app/TrustUp-API/blob/main/docs/architecture/database-schema.md

Dependencies:

• Issue User Notifications List Endpoint #60 (List notifications) should be implemented
• Issue Mark Notifications as Read Endpoints #61 (Mark as read) should be implemented

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🗒️ Additional notes

Acceptance Criteria:

• All test cases pass
• Code coverage for NotificationsService is at least 80%
• Database operations are properly mocked
• Filtering and pagination logic is validated
• Ownership validation is tested
• Edge cases (empty lists, invalid IDs) are covered