fix(team-analytics): resolve single-day date range filtering issue

This MR fixes a date filtering issue in Contribution Mapping → Team Analysis where contributions were not displayed for single-day or narrow date ranges.

Previously:

Date ranges like 2026-02-20 → 2026-02-22 worked correctly.

But 2026-02-21 → 2026-02-22 returned zero contributions even when commits, merge requests, and issues existed on those dates.

Root Cause

The end date was not treated as inclusive. It was interpreted as YYYY-MM-DD 00:00:00, which excluded contributions created later on the end date.

Fix

Updated date filtering logic to properly include the full end date.

Ensured commits, MRs, and issues are filtered correctly for:

Single-day ranges

Narrow ranges

Multi-day ranges

Verified accurate totals and summary table output.This improves reliability and correctness of team analytics.

References

Closes: Single-day date filtering issue in Team Contribution Mapping