* fix(jellycompat): return seasons/episodes when browsing a series via /Items?ParentId=
Clients that browse a show through the generic /Items?ParentId= endpoint with no
IncludeItemTypes (e.g. the VoidTV Android-TV client's getSeasons/getEpisodes) got
the top-level library views instead of the series' seasons or the season's
episodes. HandleItems only honored an item/season ParentId when
IncludeItemTypes=Season was present and otherwise fell through to the
library-views fallback (or a global type browse), so ParentId was effectively
ignored.
Decode a season ParentId into its own parentSeasonID and route item parents:
- season ParentId -> that season's episodes
- series ParentId -> the series' seasons (or its episodes for
IncludeItemTypes=Episode; an unsatisfiable type filter returns an empty page)
Extract the shared writeSeriesEpisodesResponse used by /Shows/{id}/Episodes and
the new browse paths. The generic /Items browse paths honor StartIndex/Limit
(matching the /Items contract and the sibling seasons listing) while
/Shows/{id}/Episodes keeps its existing whole-season response.
Adds parent_browse_test.go covering series->seasons, season->episodes, the
unsatisfiable-type-filter empty case, paging, and the parser's season/item
ParentId distinction.
* fix(jellycompat): empty result for non-episode type filter on a season ParentId
handleSeasonEpisodeChildren ignored IncludeItemTypes and always returned the
season's episodes. A season's only children are episodes, so a type filter that
excludes Episode (e.g. IncludeItemTypes=Movie) now returns an empty page,
mirroring the series-parent path's handling of unsatisfiable type filters.
Addresses a CodeRabbit review comment.
