Finish the opening milestone's switching, items and acceptance run

- Decode evolution lists from the ROM; all 251 match the pinned PRET source.
- Compare CalcMonStats and CalcExpAtLevel against the original routines in
  the reference emulator.
- Add a continuous opening playthrough from the intro to the catching
  tutorial, reloading a JSON save after every stage.
- Port player switching in battle: the PKMN menu, forced choices after a
  faint, Shift mode's offer and double faints, with the original texts.
- Port HP and status healing items in battle through the ROM's ItemEffects,
  HealingHPAmounts and StatusHealingActions tables.
- Add the battle party menu and the Items pocket to the UI.

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

src/game/rom/pokemon.ts

@@ -38,6 +38,25 @@ export interface MoveData {
 /** Item types, which select a bag pocket (constants/item_data_constants.asm). */
 export type Pocket = "item" | "key" | "ball" | "tm";
 const POCKETS: readonly Pocket[] = ["item", "key", "ball", "tm"];
+/** One entry of a species' evolution list (data/pokemon/evos_attacks.asm).
+ * A trade's `item` is null for the ROM's -1 (no held item needed). */
+export type Evolution =
+  | { method: "level"; level: number; species: number }
+  | { method: "item"; item: number; species: number }
+  | { method: "trade"; item: number | null; species: number }
+  | {
+      method: "happiness";
+      time: "anytime" | "mornday" | "nite";
+      species: number;
+    }
+  | {
+      method: "stat";
+      level: number;
+      attack: "gt" | "lt" | "eq";
+      species: number;
+    };
+const HAPPINESS_TIMES = ["anytime", "mornday", "nite"] as const;
+const STAT_TRIGGERS = ["gt", "lt", "eq"] as const;
 
 /** Decoders for species, moves and items. All data is read from the
  * user's ROM on demand and cached in memory only. */
@@ -175,6 +194,53 @@ export class PokemonData {
     };
   }
 
+  /** The evolution list before the learnset, in ROM order (EvolveAfterBattle
+   * tries entries in this order). EVOLVE_STAT records are four bytes long;
+   * the others three. */
+  evolutions(species: number): Evolution[] {
+    this.checkSpecies(species);
+    const r = this.reader;
+    let p = r.near(
+      SYMBOLS.evosAttacks + (species - 1) * 2,
+      r.bank(SYMBOLS.evosAttacks),
+    );
+    const evolutions: Evolution[] = [];
+    for (let method = r.byte(p); method !== 0; method = r.byte(p)) {
+      if (evolutions.length > 8) throw new Error("Invalid evolution data.");
+      const a = r.byte(p + 1);
+      let evolution: Evolution;
+      if (method === 1)
+        evolution = { method: "level", level: a, species: r.byte(p + 2) };
+      else if (method === 2)
+        evolution = { method: "item", item: a, species: r.byte(p + 2) };
+      else if (method === 3)
+        evolution = {
+          method: "trade",
+          item: a === 0xff ? null : a,
+          species: r.byte(p + 2),
+        };
+      else if (method === 4) {
+        const time = HAPPINESS_TIMES[a - 1];
+        if (!time) throw new Error("Invalid evolution data.");
+        evolution = { method: "happiness", time, species: r.byte(p + 2) };
+      } else if (method === 5) {
+        const attack = STAT_TRIGGERS[r.byte(p + 2) - 1];
+        if (!attack) throw new Error("Invalid evolution data.");
+        evolution = {
+          method: "stat",
+          level: a,
+          attack,
+          species: r.byte(p + 3),
+        };
+        p++;
+      } else throw new Error("Invalid evolution data.");
+      this.checkSpecies(evolution.species);
+      evolutions.push(evolution);
+      p += 3;
+    }
+    return evolutions;
+  }
+
   /** Level-up moves (data/pokemon/evos_attacks.asm). Like FillMoves, the
    * evolution list is skipped up to its terminating zero byte. */
   learnset(species: number): { level: number; move: number }[] {

src/game/rom/profile.ts

@@ -157,6 +157,7 @@ export const RAM = {
   callerContact: 0xd03f,
   surfingPlayerState: 0xd1eb,
   strengthSpecies: 0xd1ef,
+  curHPAnimDeltaHP: 0xd1f3,
   /** hMoneyTemp: HRAM, not WRAM like the other entries above. */
   moneyTemp: 0xffc3,
 } as const;
@@ -468,6 +469,32 @@ export const BATTLE = {
   HasNoPPLeftText: 0x80fba,
   HeldStatusHealingEffects: 0x3de44,
   HPIsFullText: 0x81534,
+  DoItMonText: 0x3f2d8,
+  GoForItMonText: 0x3f2df,
+  YourFoesWeakGetmMonText: 0x3f2e6,
+  "WithdrawMonText.WithdrawMonText": 0x3f2fa,
+  ThatsEnoughComeBackText: 0x3f348,
+  OKComeBackText: 0x3f34d,
+  GoodComeBackText: 0x3f352,
+  ComeBackText: 0x3f35b,
+  BattleText_UseNextMon: 0x80a83,
+  BattleText_MonIsAlreadyOut: 0x80c0d,
+  BattleText_MonCantBeRecalled: 0x80c22,
+  BattleText_TheresNoWillToBattle: 0x80b0b,
+  BattleText_AnEGGCantBattle: 0x80b26,
+  BattleText_EnemyIsAboutToUseWillPlayerChangeMon: 0x80aca,
+  ChooseAMonString: 0x504e4,
+  WhichPKMNString: 0x50504,
+  ItemEffects: 0xe73c,
+  RestoreHPEffect: 0xf186,
+  StatusHealingEffect: 0xefcc,
+  StatusHealingActions: 0xf071,
+  HealingHPAmounts: 0xf3af,
+  "PrintPartyMenuActionText.MenuActionTexts": 0x5057b,
+  ItemWontHaveEffectText: 0xf81f,
+  ItemCantUseOnEggText: 0xf810,
+  OakThisIsntTheTimeText: 0x10af3,
+  UseOnWhichPKMNString: 0x504f3,
   HungOnText: 0x80e99,
   HurtByBurnText: 0x807f8,
   HurtByPoisonText: 0x807e2,