perf: optimize unread notification count query

[Ayush-0918]

Pull Request

Summary

Optimized the unread notification count by replacing the previous implementation, which loaded unread notifications into memory, with a SQL COUNT(*) query for better performance.

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Related Issue

Closes #199

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Type of Change

• Performance improvement

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Changes Made

• Replaced the unread notification query with SELECT COUNT(*).
• Used SQLAlchemy func.count() instead of loading all unread notification objects.
• Preserved existing behavior while reducing unnecessary database load.

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Screenshots (if applicable)

N/A

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Testing

• Tested locally
• Existing tests pass
• Added new tests
• UI verified
• Cross-browser tested (if applicable)

Additional testing notes:

• Verified the query logic after replacing object loading with SQL COUNT(*).

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Checklist

• My code follows the project's coding standards.
• I have tested my changes locally.
• I have updated the documentation where necessary.
• My changes do not introduce new warnings or errors.
• I have reviewed my own code.
• This pull request focuses on a single feature or fix.
• I have linked the related issue.

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Additional Notes

This change only optimizes the unread notification count query. No functional behavior has been modified.

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[nensii21]

attached videos and screenshots showing what changes have been made also some CI jobs are failing update it.