Replace mobile touch overlay with a coin-door-styled bottom control bar

The engine's default attachTouchControls() overlay was generic floating
circles; this swaps in an app-themed bottom bar (left/right flipper,
plunger, insert coin, start game) anchored to the screen edges instead.

components/pinball/PinballCanvasImpl.tsx

@@ -2,8 +2,8 @@
 
 import { useRef } from "react";
 import { usePinballInstance, type RomSelection } from "@/lib/pinball/usePinballInstance";
-import { useTouchControls } from "@/lib/pinball/useTouchControls";
 import CoinDoorHud from "@/components/hud/CoinDoorHud";
+import TouchControlBar from "@/components/hud/TouchControlBar";
 import type { TableInfo } from "@/lib/pinball/types";
 
 export interface PinballCanvasImplProps {
@@ -14,16 +14,14 @@ export interface PinballCanvasImplProps {
 
 export default function PinballCanvasImpl({ tableData, rom, tableInfo }: PinballCanvasImplProps) {
   const canvasRef = useRef<HTMLCanvasElement | null>(null);
-  const containerRef = useRef<HTMLDivElement | null>(null);
   const { status, progress, error, loadTimeMs, instanceRef, start } = usePinballInstance(
     canvasRef,
     tableData,
     rom,
   );
-  useTouchControls(containerRef, status === "running");
 
   return (
-    <div ref={containerRef} className="relative h-full w-full overflow-hidden bg-black">
+    <div className="relative h-full w-full overflow-hidden bg-black">
       {/* SDL3's Emscripten backend resolves its own window/GL-context target via
           document.querySelector("#canvas") independently of Module.canvas — the
           id is required or context creation silently no-ops (findCanvasEventTarget
@@ -35,6 +33,8 @@ export default function PinballCanvasImpl({ tableData, rom, tableInfo }: Pinball
         <CoinDoorHud instanceRef={instanceRef} tableInfo={tableInfo} loadTimeMs={loadTimeMs} />
       )}
 
+      <TouchControlBar active={status === "running"} />
+
       {status === "loading" && (
         <div className="absolute inset-0 flex flex-col items-center justify-center gap-4 bg-ink/90 text-paper">
           <div className="font-display text-2xl tracking-wide text-marquee">LOADING TABLE</div>