Legal pages, Threads OAuth, live wallet pill, PvP money flow + resume

- Legal: /privacy-policy and /datadeletion (shared LegalPageLayout, footer
  links, sitemap + integration tests, NEXT_PUBLIC_LEGAL_CONTACT_EMAIL).
- Threads OAuth: server-side /api/threads-exchange and /threads-callback
  page (Suspense + client component, noindex, no leaked secrets).
- Username + live wallet pill in top nav. New NavWalletBalance component
  polls /api/wallet, refreshes on tab focus, and listens to the
  `wallet:refresh` event bus so cash-outs and refunds update the nav in
  real time. Flash animation on balance changes.
- useLiveWalletBalance hook now broadcasts `wallet:refresh` after every
  fetch so games, exchange panel, wallet actions, and nav all stay in
  sync without extra polling.
- PvP fund-locking (`POST /api/games/rooms`): creator funds debited
  atomically with room creation; ledger entry tagged with `gameRoomId`.
  Joiner debit happens at join. Old double-debit of the creator is gone.
- DELETE /api/games/rooms?id=... lets a creator cancel a WAITING room
  and get an idempotent refund. Coin Flip + Pong waiting screens show a
  Cancel & Refund button.
- Pong/Coin Flip recovery: expiry sweep + boot-time `recoverOrphaned
  RoomsOnBoot()` (runs before listen()) refund both parties for any
  ACTIVE/expired rooms so a server restart never strands locked credits.
- Schema migration `20260520000000_game_ledger_links` adds optional
  `gameSessionId` + `gameRoomId` FKs to LedgerEntry (with indexes) and
  extra indexes on GameSession/GameRoom for resume + sweep queries.
- GET /api/games/active returns a user's active solo session + open
  rooms (sanitized — no mine/bomb positions). Mines and Tower clients
  rehydrate on mount so a refresh mid-round resumes instead of dropping.
- ActiveGamesBanner surfaces unfinished rounds on /wallet and /casino
  with Resume / Rejoin / Cancel & refund actions.
- ExchangePanel unified with useLiveWalletBalance; per-game header gets
  an "Open wallet →" chip; Dice clears stale result on roll; Blackjack
  reveals full dealer hand on natural blackjack/push; Mines refund
  label fixed; Tower final multiplier fixed; GameHistory error path;
  Prediction "Resolved" tab.
- Site audit + redmeFIXES triage notes (REDME-FIXSES-TRIAGE.txt,
  SITE-AUDIT.txt).

Co-authored-by: Cursor <cursoragent@cursor.com>

src/auth.ts

@@ -53,6 +53,7 @@ export const { handlers, auth, signIn, signOut } = NextAuth({
           id: user.id,
           email: user.email,
           name: user.name ?? undefined,
+          username: user.username,
           role: user.role,
         };
       },
@@ -62,14 +63,18 @@ export const { handlers, auth, signIn, signOut } = NextAuth({
     jwt({ token, user }) {
       if (user) {
         token.id = user.id;
-        token.role = (user as { role: string }).role;
+        if (user.username) token.username = user.username;
+        const role = (user as { role?: string }).role;
+        token.role = role === "ADMIN" || role === "USER" ? role : "USER";
       }
       return token;
     },
     session({ session, token }) {
       if (session.user) {
         session.user.id = (token.id as string) ?? (token.sub as string);
-        session.user.role = (token.role as "USER" | "ADMIN") ?? "USER";
+        if (typeof token.username === "string") session.user.username = token.username;
+        const role = token.role;
+        session.user.role = role === "ADMIN" || role === "USER" ? role : "USER";
       }
       return session;
     },