v2.5.0: Phase 3 — weekly report, chart hover, clock-in distribution, leave calendar

- Weekly auto report on Monday (system alert + Discord push, dedupe)
- Matplotlib chart hover annotation for daily hours
- Clock-in time distribution histogram (30-min bins) with avg line
- Leave usage calendar with color-coded full/half/quarter days

Fixed: leave_view setLayout indentation regression

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

core/version.py

@@ -4,4 +4,4 @@
 릴리스 시 이 값을 올린 후 git tag → push.
 CHANGELOG.md의 최상단 항목과 일치시킬 것.
 """
-__version__ = '2.4.0'
+__version__ = '2.5.0'