Fix remaining multi-weekday recurrence bugs

[chrisvel]

Description

Type of Change

• Bug fix (fixes an issue)
• New feature (adds functionality)
• Breaking change (breaks existing functionality)
• Documentation/Translation update

Related Issues

Fixes #715

Testing

How did you test this?

Commands run:

• npm run pre-push (linting + formatting + tests)
• Tested manually in browser
• Tested on mobile (if UI changes)

Screenshots

Checklist

• This is not an AI slop crap, I know what I am doing
• Code follows project style guidelines
• Self-reviewed my own code
• Added/updated tests (if applicable)
• Updated documentation (if needed)
• Database migrations included and tested (if applicable)
• Translation keys added and synced (if applicable)

Additional Notes