Shoot from the volume keys, while the camera is up

App.tsx

@@ -31,6 +31,7 @@ import { LITE_FAVORITE_LIMIT, LITE_MARK, LITE_RECIPE_LIMIT, proLookInUse } from
 import { initProUnlock, useProUnlock } from './src/utils/proUnlock';
 import UltraWide from './modules/recipescam-ultrawide';
 import RecipescamExport from './modules/recipescam-export';
+import VolumeShutter from './modules/recipescam-volume';
 
 // @ts-ignore
 import './global.css';
@@ -1532,6 +1533,24 @@ export default function App() {
     }
   };
 
+  // Volume keys as a shutter release. `handleCapture` is rebuilt every render,
+  // so the listener is bound once and reaches the current one through a ref.
+  const captureFromKeyRef = useRef(handleCapture);
+  captureFromKeyRef.current = handleCapture;
+  useEffect(() => {
+    const sub = VolumeShutter.addListener('onShutter', () => {
+      void captureFromKeyRef.current();
+    });
+    return () => sub.remove();
+  }, []);
+  // Only the camera screen claims the keys; everywhere else (the library)
+  // they stay volume keys.
+  // ponytail: keyed off the mode alone, so a press behind a modal still
+  // takes a frame - add the overlay flags here if that ever bites.
+  useEffect(() => {
+    VolumeShutter.setEnabled(mode === 'camera');
+  }, [mode]);
+
   // Held-shutter burst: press and hold the shutter, frames keep coming until
   // the finger lifts. Every frame is a normal capture (GPS resolve, RAW rules,
   // background render enqueue), so a burst photo is indistinguishable from a