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/ui/shell.ts

@@ -35,6 +35,8 @@ export function renderShell(root: HTMLElement) {
                 <div id="battle-player" class="battle-player"><canvas id="battle-player-pic" width="48" height="48" role="img"></canvas><div class="battle-hud"><div><strong id="battle-player-name"></strong><span id="battle-player-level"></span></div><div class="hp-row"><span>HP</span><span class="hp-bar"><i id="battle-player-hp"></i></span></div><div class="battle-numbers"><span id="battle-player-status" class="battle-status"></span><span id="battle-player-hp-text"></span></div></div></div>
                 <div class="battle-box"><p id="battle-text" aria-live="polite"></p><div id="battle-menu" class="battle-menu"></div></div>
               </div>
+              <div id="town-map-view" class="town-map-view" hidden aria-label="Town Map"><canvas id="town-map-canvas" width="160" height="144" role="img" aria-label="Town Map"></canvas><button id="town-map-close">Close map</button></div>
+              <div id="field-menu" class="field-menu" hidden aria-label="Pack"><p>KEY ITEMS</p><div id="field-items"></div></div>
               <div id="mart" class="mart" hidden aria-label="Poké Mart">
                 <p id="mart-money" class="mart-money"></p>
                 <div class="mart-box"><p id="mart-prompt" aria-live="polite"></p><div id="mart-menu" class="mart-menu"></div></div>