SCRUM-325: fix(rewards) add null safety and unit tests for GetRewardAnalyticsQuery

[Moha-sami]

Summary

Follow-up fix for Jemy's PR #369 (\SCRUM-325-REWARD-EP-6).

Changes

• Null Safety:
  • Made \RewardTransactionFilterQueryDto? Filter\ optional and defaulted parameters to null.
  • Added fallback \�ar filter = query.Filter ?? new RewardTransactionFilterQueryDto();\ in \GetRewardAnalyticsQueryHandler\ to prevent NRE.
  • Added inverted date range normalization in \ResolveDateBounds\ (\if (from > to) (from, to) = (to, from)).
  • Added .Include(r => r.Employee).ThenInclude(e => e.JobRole).ThenInclude(j => j!.Department)\ and safe navigation property checks in \BuildTransactionsAsync.
  • Added null check on
    .PointsTransaction != null ? Math.Abs(r.PointsTransaction.Amount) : 0.
• Unit Tests:
  • Added 7 unit tests in \GetRewardAnalyticsQueryTests.cs\ covering 404 Not Found, default monthly timeline, weekly timeline aggregation, search filtering, null filters, inverted dates, and controller endpoint mappings.
  • Verified 726/726 tests pass locally.

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Project	Deployment	Actions	Updated
hr-system	Ready	Preview	Sep 18, 2026 12:58am UTC

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