#3835 final miscellaneous changes

[JoshuaGoldberg]

Changes

A bunch of small changes and old file deletion (more info soon)

Includes:

Typo fixes

Removal of old calendar files

Hooking up edit/delete modals to the table

Backend logic fixes

Other minor bug fixes to filtering etc.

Probably a few extra things too.

Notes

Hopefully this resolves a majority of remaining issues!

Test Cases

N/A

Screenshots

Not terribly applicable since it's a bunch of minor things

To Do

Check for anything else that's missing

Availability merge in/final changes

Checklist

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• All commits are tagged with the ticket number
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• All code follows repository-configured prettier formatting
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• All checks passing
• Screenshots of UI changes (see Screenshots section)
• Remove any non-applicable sections of this template
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Closes # (issue #)