feat(api): terms filter on list item and watchlist routes

[rectifyer]

Note

Stacked on #965 (feat/lists_search), which introduces termsQuerySchema. Review and merge that first; this PR's base retargets to master once it merges.

Summary

Documents the optional terms query param on the list item and watchlist routes, which the API now supports. When set, only items whose title contains the text are returned, case-insensitively: the movie or show title, the parent show's title for seasons, the show or episode title for episodes, and a person's name. Part of list search for trakt/trakt-web#1701.

Changes

termsQuerySchema is merged into the query schema of every item-returning list and watchlist route:

Contract	Routes
users.lists.list.items	movie, show, media, all, typedSorted
users.watchlist	movies, shows, media, typedSorted

No other schemas change.

Release

Additive and non-breaking: existing callers compile and behave as before. It can ship in the same patch tag as #965 (v0.6.1).

trakt-web does not have to wait for the release. The client serializes the query object without validating it, so terms already goes out on 0.6.0. The bump only adds typed access.

Verification

• deno check src/index.ts, deno fmt and deno lint pass.
• deno task publish:check completes its dry run with Success.