* implemented logo customization for single-user mode
* removing unneeded comments
* added dark and light mode support for default logo
* implemented dark and light mode switching in frontend
* fixed dark and light mode switching for failed to load logo from backend
* removed unneeded comment
* custom logos for admin implemented
* refactor logo mgmt functions
abstract logo management utils into their own file for simplicity
* added settings tab for appearance on single-user mode
* unchecking files with unneeded changes
* fixed appearance settings tab to be hidden on multiuser mode
* allow readall for logo
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Co-authored-by: timothycarambat <rambat1010@gmail.com>
