[Suggestion] Implement more navigation features and keybinds to the webui

[Asinin3]

LRR's webui is pretty great, but there's a few changes I'd like to see.

• Add a Keybind for opening a random archive, bit of a pain to have to scroll down every time to click on the button until you find something interesting.
• Make the view random gallery button only open galleries that were found with search terms used from the index page
• Add a button/keybind to go to the next/previous alphabetically sorted gallery. Useful when reading series of chapters.

[Salvora]

adding a clickable link to the "reader view" for easily returning the library would be appreciated.

[Difegue]

The downward arrow at the bottom of the page does that 👍

[Salvora]

Oh, I missed that since I tried the infinite scrolling. It is kinda hard to navigate there. Is it possible to put it next to this place?

[psilabs-dev]

[ ] Add a button/keybind to go to the next/previous alphabetically sorted gallery. Useful when reading series of chapters.

PR #1214 (read previous/next) aims to tackle the third one. It has more generalized functionality than alphabetical sorting, since it uses the underlying datatables result to form a reading list.