[frontend] Unified panels (#812)
* settings panel restructuring
* clean up old Gin handlers
* colorscheme redesign, some other small css tweaks
* basic router layout, error boundary
* colorscheme redesign, some other small css tweaks
* kebab-case consistency
* superfluous padding on applist
* remove unused consts
* redux, whitespace changes..
* use .jsx extensions for components
* login flow up till app registration
* full redux oauth implementation, with basic error handling
* split oauth api functions
* oauth api revocation handling
* basic profile change submission
* move old dir
* profile overview
* fix keeping track of the wrong instance url (for different instance/api domains)
* use redux state for profile form
* delete old/index.js, old/basic.js, fully implemented
* implement old/user/profile.js
* implement password change
* remove debug logging
* support future api for removing files
* customize profile css
* remove unneeded wrapper components
* restructure form fields
* start on admin pages
* admin panel settings
* admin settings panel
* remove old/admin files
* add top-level redirect
* refactor/cleanup forms
* only do API checks on logged-in state
* admin-status based routing
* federation block routing
* federation blocks
* upgrade dependencies
* react 18 changes
* media cleanup
* fix useEffect hooks
* remove unused require
* custom emoji base
* emoji uploader
* delete last old panel files
* sidebar styling, remove unused page
* refactor submit functions
* fix sidebar boxshadow-border
* fix old css variables
* fix fake-toot avatar
* fix non-square emoji
* fix user settings redux keys
* properly get admin account contact from instance response
* Account.source default values
* source.status_format key
* mobile responsiveness
* mobile element tweaks
* proper redirect after removing block
* add redirects for old setting panel urls
* deletes
* fix mobile overflow
* clean up debug logging calls
938328cd07