Implement calendar display with multi-day event support

- Added timezone support (Pacific/Auckland) for calendar events
- Implemented recurring event handling using recurring_ical_events library
- Created horizontal 5-day column layout for calendar display
- Fixed multi-day event rendering to show events across all active days
- Updated calendar to show next 5 days (today + 4)
- Reduced font sizes and padding for compact display
- Changed image rotation interval to 60 seconds
- Added pytz and recurring_ical_events dependencies

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

requirements.txt

@@ -1,7 +1,5 @@
 Flask==3.0.0
-google-auth==2.25.2
-google-auth-oauthlib==1.2.0
-google-auth-httplib2==0.2.0
-google-api-python-client==2.110.0
 requests==2.31.0
 python-dotenv==1.0.0
+pytz==2024.1
+recurring_ical_events==3.8.0