feat(api): add awardKind filter and multi-game filtering to player-games

[wescopeland]

This PR adds a filter[awardKind] and comma-delimited filter[gameId] support to the V2 player-games resource, which covers the beaten portion of API_GetUserCompletedGames and provides a replacement pathway from API_GetUserProgress.

GET /api/v2/users/{user}/player-games?filter[awardKind]=beaten-casual,beaten-hardcore
GET /api/v2/users/{user}/player-games?filter[gameId]=1,2,3&include=game

Things worth noting:

• filter[awardKind] accepts beaten-casual and beaten-hardcore, matching the user-awards filter[kind] vocab.
• Completion/mastery are deliberately absent because that is set-level data.
• Unknown filter values return a 400.
• filter[gameId] now accepts a comma-delimited list, so V1's multi-game API_GetUserProgress map is a single V2 request.

[greptile-apps]

Confidence Score: 5/5

Safe to merge — the new filter logic is correct and well-tested.

The badge-based fallback query correctly adds the user_id column constraint that the relationship omits, the OR grouping prevents filter bleed, unknown values return 400, and test coverage is thorough across all new paths.

No files require special attention.

_{Reviews (6): Last reviewed commit: "Merge branch 'master' into v2-player-gam..." | Re-trigger Greptile}