Complete the overworld foundation

Port forced movement (turn delays, bumps, ice, currents, pits), dynamic
return warps, elevators, Surf, Cut, Strength and cycling rules, working
map blocks with changeblock/changemapblocks, and the remaining NPC
movement types and movement commands.

Add tileset animation from the ROM's command tables, grass sprite
priority and special map palettes; room decorations with ownership, the
bedroom PC and save migration; and Key Items access to the Bicycle.

Fourteen original-engine traces compare positions, facing, actors, event
flags and scripted poses. Tile animation matches original VRAM for four
tilesets, and LoadMapPals matches 192 palette cases. skyfall_top now
keeps the $60 sprite offset its step function leaves behind.

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

src/game/runtime.ts

@@ -9,6 +9,7 @@ import { WorldRenderer } from "./rendering/renderer";
 export class NativeRuntime implements GameRuntime {
   readonly id = "crystal-native-world-v1";
   world?: GameWorld;
+  fieldMenuOpen = false;
   private renderer?: WorldRenderer;
   private pressed = new Set<Button>();
   private raf = 0;
@@ -26,6 +27,7 @@ export class NativeRuntime implements GameRuntime {
   ) {}
   async load(bytes: Uint8Array, canvas: HTMLCanvasElement) {
     this.dispose();
+    this.fieldMenuOpen = false;
     const assets = new CrystalAssets(bytes);
     const world = new GameWorld(assets);
     const player = this.player();
@@ -57,20 +59,28 @@ export class NativeRuntime implements GameRuntime {
     if (this.pressed.has(button) || !this.world) return;
     this.pressed.add(button);
     const world = this.world;
-    if (world.battle && this.battleInput?.(button)) {
+    if (this.battleInput?.(button)) {
       this.publish();
       return;
     }
     if (button === "a") world.interact();
     if (button === "b") world.advanceDialogue();
-    if (["up", "down", "left", "right"].includes(button) &&
-        (world.dialogue?.choice || world.battle?.prompt?.kind === "yesno"))
+    if (
+      ["up", "down", "left", "right"].includes(button) &&
+      (world.dialogue?.choice || world.battle?.prompt?.kind === "yesno")
+    )
       world.moveCursor(button as Direction);
     if ((button === "start" || button === "select") && !world.busy)
       world.notice =
         "Use the Savegames tab to save, export or import. Party, pack and Pokégear menus are not ported yet.";
     this.publish();
   }
+  useBicycle() {
+    this.fieldMenuOpen = false;
+    if (this.world && !this.world.useBicycle())
+      this.world.notice = "You can’t use the BICYCLE here.";
+    this.publish();
+  }
   /** Answer a choice from a pointer or keyboard control outside the canvas. */
   choose(answer: number | string) {
     this.world?.choose(answer);
@@ -108,7 +118,7 @@ export class NativeRuntime implements GameRuntime {
       let ticks = 0;
       while (this.pending >= 1 / TICKS_PER_SECOND && ticks < 6) {
         this.pending -= 1 / TICKS_PER_SECOND;
-        world.tick(held);
+        if (!this.fieldMenuOpen) world.tick(held);
         ticks++;
       }
       if (ticks === 6) this.pending = 0;
@@ -225,6 +235,7 @@ export class NativeRuntime implements GameRuntime {
   restoreState(bytes: Uint8Array) {
     if (!this.world || bytes.length > 64_000)
       throw new Error("Invalid native save size.");
+    this.fieldMenuOpen = false;
     this.world.restore(
       JSON.parse(new TextDecoder("utf-8", { fatal: true }).decode(bytes)),
     );