feat(codes): mark a code dead once the owner confirms it in game

Game8 still lists Y1INABQB6DEX, 2BJ64QRZ7RT8 and PLDXIB886Y1S as active
Genshin codes after the game refused them. CODE_CHECKS records the
owner's in-game check; build-codes stamps the matching code confirmedDead,
and the Codes tab shows it expired: "Confirmed expired in game, 2026-10-20."

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

src/shared/codeChecks.ts

@@ -0,0 +1,25 @@
+import type { GameId } from "./schema.ts";
+
+/**
+ * Codes the repository owner tried in game and found dead, while the source
+ * still lists them as active (owner, 2026-10-20). The in-game check is the
+ * evidence, as for a routine marked `Confirmed in game` (`routines.ts`): the
+ * reader sees "Confirmed expired in game, YYYY-MM-DD." on the code.
+ *
+ * Only "dead" is recorded; there is no "still works". An entry whose code the
+ * source has since dropped matches nothing and is logged by `build-codes`, so
+ * prune it whenever convenient.
+ */
+export interface CodeCheck {
+  game: GameId;
+  /** Exactly as the source spells it. */
+  code: string;
+  /** The day it was tried and refused. */
+  checked: string;
+}
+
+export const CODE_CHECKS: readonly CodeCheck[] = [
+  { game: "genshin", code: "Y1INABQB6DEX", checked: "2026-10-20" },
+  { game: "genshin", code: "2BJ64QRZ7RT8", checked: "2026-10-20" },
+  { game: "genshin", code: "PLDXIB886Y1S", checked: "2026-10-20" },
+];

src/shared/codes.ts

@@ -12,6 +12,15 @@ export const RedeemCodeSchema = z.object({
     .regex(/^\d{4}-\d{2}-\d{2}$/)
     .nullable()
     .optional(),
+  /**
+   * The day the repository owner tried the code in game and it no longer
+   * worked (`codeChecks.ts`). Only ever "dead": the source still supplies the
+   * code, its reward and its link.
+   */
+  confirmedDead: z
+    .string()
+    .regex(/^\d{4}-\d{2}-\d{2}$/)
+    .optional(),
   firstObservedAt: z.string().datetime(),
   sourceUrl: z.string().url(),
 });