Port field moves from the menu, SEL with Select, and moving Pokémon in Bill's PC

Field moves chosen in the party menu run their original checks and the
ROM's from-menu scripts (Cut, Surf, Strength, Flash, Whirlpool, Waterfall,
Sweet Scent), and Softboiled and Milk Drink share HP. SEL registers a key
item that Select then uses, replacing the Key Items shortcut, and Bill's
PC moves Pokémon between the party and every box.

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

src/ui/shell.ts

@@ -33,7 +33,6 @@ export function renderShell(root: HTMLElement) {
               </div>
               <div id="stats-screen" class="stats-screen" hidden aria-label="Pokémon stats"><div class="stats-top"><canvas id="stats-pic" width="56" height="56" role="img"></canvas><div id="stats-header" class="stats-header"></div></div><div id="stats-page" class="stats-page" aria-live="polite"></div><div class="stats-nav"><button id="stats-prev" aria-label="Previous page">◀</button><span id="stats-page-number"></span><button id="stats-next" aria-label="Next page">▶</button><button id="stats-close">Close</button></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-tabs" class="pack-tabs" aria-label="Pockets" hidden></div><div id="mart-menu" class="mart-menu"></div></div>

src/ui/styles.css

@@ -1117,30 +1117,6 @@ dialog dd {
   }
 }
 
-.field-menu {
-  position: absolute;
-  inset: 1rem 1rem auto auto;
-  z-index: 6;
-  max-height: calc(100% - 2rem);
-  overflow: auto;
-  min-width: 10rem;
-  padding: 1rem;
-  border: 2px solid #27332a;
-  border-radius: 0.4rem;
-  background: #f8f4df;
-  color: #27332a;
-}
-.field-menu[hidden] {
-  display: none;
-}
-.field-menu p {
-  margin: 0 0 0.5rem;
-}
-#field-items {
-  display: grid;
-  gap: 0.3rem;
-}
-
 .town-map-view {
   position: absolute;
   inset: 0;