Port the remaining battle items, the stats screen and hBattleTurn at the menu

- Run every non-ball item effect usable in battle from the ROM's
  ItemEffects: Full Restore, revives, bitter medicine, Bitter Berry, Ethers
  and Elixers, X items, X Accuracy, Guard Spec, Dire Hit and Poké Doll.
- Read happiness changes from HappinessChanges, including the larger
  level-up gain where a Pokémon was caught.
- Model hBattleTurn at the battle menu, including the trainer AI's writes,
  and drop the status-heal refusal.
- Port the stats screen for battles and Bill's PC.
- Compare the send-out and withdraw texts, RestoreHealth, RestorePP,
  ChangeHappiness and CalcPlayerStats with the original routines.

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

src/game/scripts/pc.ts

@@ -494,7 +494,7 @@ export class PcSession {
           break;
         }
         if (action === SUBMENU_STATS) {
-          yield { kind: "notice", text: "The stats screen is not ported yet." };
+          yield { kind: "stats", mon: structuredClone(mon) };
           continue;
         }
         if (action !== SUBMENU_RELEASE) break;
@@ -547,7 +547,8 @@ export class PcSession {
           break;
         }
         if (action === SUBMENU_STATS) {
-          yield { kind: "notice", text: "The stats screen is not ported yet." };
+          // CalcTempmonStats: stats from stat experience, full HP, no status.
+          yield { kind: "stats", mon: withdrawnMon(this.host.data, mon) };
           continue;
         }
         if (action !== SUBMENU_RELEASE) break;