feat: add Umamusume, from Game8's banner list

uma.moe stays declined — its API sits behind a Cloudflare Turnstile proof
header, and an adapter would mean defeating a deliberate access control. This
is the surface that is simply open, and it needed the parser change in the
commit before this one to be readable at all.

The stable URL matters: Game8 also publishes monthly "August 2026 Release
Schedule" pages whose id changes every month, which a static registry cannot
follow. "List of All Banners" does not move.

Four current banners, both columns of the side-by-side table, and none of the
Previous Banners below them. The tenth game8 source, so it carries the same CI
blindness as the other nine and only a manual refresh moves it.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

src/shared/games.ts

@@ -135,6 +135,11 @@ export const GAMES: Record<GameId, GameMeta> = {
   // No `resetOffsets`: the source is Game8, which states day-precision prose
   // and no clock at all — the same silence p5x has, and the same answer.
   czn: { id: "czn", name: "Chaos Zero Nightmare", short: "CZN", hue: "#B84A9C", studio: "Smilegate", dailyTasks: "Daily missions" },
+  // No `resetOffsets`. The source's own column is headed `Availability (UTC)`,
+  // which states the zone the *dates* are in and says nothing about where the
+  // server's day rolls — and every row on it is a bare date anyway, with no
+  // time of day to read a reset out of. Same silence as p5x and czn.
+  uma: { id: "uma", name: "Umamusume: Pretty Derby", short: "Umamusume", hue: "#6FBF44", studio: "Cygames", dailyTasks: "Daily races, missions" },
 };
 
 export const GAME_LIST: GameMeta[] = Object.values(GAMES);