Review follow-up to c0e9229. handleLibraryAuthors and handleLibrarySeries
fetched the page slice and reported len(results) as total, hiding the
next-page button for libraries with > 50 authors / > 25 series. Both
now over-fetch (cap 5000) and paginate locally so total is the real DB
row count. Also adds the "tags" key (and confirms "genres") on the play
session mediaMetadata map so strict 3rd-party clients dont crash on
undefined; this completes the empty-array guarantee Task 4 began on the
browse/detail surface. Strengthens the series slug test to pin actual
slugify output.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
