v2.6.0 - Tag Editor Suggestions

✨ Added

• The tag editor suggests the library's existing publishers, imprints, series,
  volumes, credits, story arcs, universes and tags as you type, so a correction
  can pick the spelling already in use instead of creating a near-duplicate.
  Imprint, series and volume suggestions narrow to the publisher, imprint and
  series chosen above them. New names can still be typed in.
• New Add Library server folder picker component.

♻️ Changed

• Renamed files carry the full date, like (1950-11-01), and the volume count
  (comicbox 5.6.0).
• Change docs to use Zensical instead of MkDocs.

🐛 Fixed

• Filenames supply the month, day, volume count and publisher; (Digital) or
  (DC) alone no longer read as the title (comicbox 5.6.0).
• A new visitor's first page load no longer sometimes fails.
• Unchecking every default metadata format no longer breaks online tagging.
• Unreadable folders in Add Library say "Permission denied" instead of "Server
  Error".