Frontend Improvements

[Genau6502]

This PR adds various improvements and small quality of life improvements to the Frontend, with limited changes to permissions as required:

• Separate the event and people pages. People requires a new see_people permission: granted to prefects. See attached images:

• Changes to rendering of events and people edit pages with certain permissions to reduce clutter on the page. The remove/edit event buttons only show if you have the relevant permissions. The edit person page now requires the edit_person permission for access

• Navbar fixed at top of screen with responsive behaviour. Fixed background colour of the navbar to ensure that on mobile it blocks content when expanded

• Fixed CSV import/export page access links
• Moved development tools to a dropdown to reduce clutter

[BurntNail]

@Genau6502 looks mostly good apart from changing the image role - maybe check with the HoH closer to the start of next year? This was part of the originally agreed design with the HoH from last year.

[Genau6502]

Fixed

[BurntNail]

I’m assuming that it all compiles etc, so lgtm!