v2.6.0: Phase 3 + Phase 4 — accessibility + code sign infra

Phase 3 (also v2.5.0 in CHANGELOG):
- Weekly auto report on Monday
- Matplotlib chart hover annotation
- Clock-in time distribution histogram
- Leave usage calendar with color coding

Phase 4 (v2.6.0):
- Font scale 100/125/150% (instant apply)
- High-contrast mode (black bg + yellow text)
- Authenticode signing infra in release.ps1 (env-gated, optional)

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

core/database.py

@@ -653,8 +653,11 @@ class Database:
             'discord_notif_clock_out': 'true',
             'discord_notif_health': 'true',
             # v2.4.0
-            'goal_overtime_max_monthly': '0',  # 0=비활성, >0=분 단위 상한
-            'goal_avg_hours_daily': '0',  # 0=비활성
+            'goal_overtime_max_monthly': '0',
+            'goal_avg_hours_daily': '0',
+            # v2.6.0
+            'font_scale': '1.0',
+            'high_contrast': 'false',
         }
 
         conn = self.get_connection()

core/settings_keys.py

@@ -37,6 +37,8 @@ THEME = 'theme'
 TIME_FORMAT = 'time_format'
 LANGUAGE = 'language'
 OVERTIME_UNIT = 'overtime_unit'
+FONT_SCALE = 'font_scale'  # '1.0' / '1.25' / '1.5'
+HIGH_CONTRAST = 'high_contrast'
 
 # 통합/외부
 DB_PATH_OVERRIDE = 'db_path_override'

core/version.py

@@ -4,4 +4,4 @@
 릴리스 시 이 값을 올린 후 git tag → push.
 CHANGELOG.md의 최상단 항목과 일치시킬 것.
 """
-__version__ = '2.5.0'
+__version__ = '2.6.0'