Updated book limits to be more generous

Big polish pass so MoodReads feels smoother on Firefox:

Fixed panel scrolling so you can actually read the full metadata
Fixed tooltip behavior so field descriptions show on top (not hidden behind page elements)
Fixed share menu behavior and improved share UX
Copy link now copies the MoodReads web app book URL when we have a match
Updated upgrade links to the correct page: https://www.moodreads.app/upgrade
Premium panel update: added Vibes and renamed Pacing to Story Pacing
Added a new link to view all 40+ fields on moodreads.app

Bug fixes

UX upgrades!