Add CANCEL to the watermark editor, scope the mark's touch layer to that editor, and stop a library frame following the user onto the camera

The custom watermark captured EVERY image touch whenever the chip was ON
with text, in both modes: after switching from a library photo to the
camera there was no way to give the image back to tap-to-focus, and a
frame picked for the still rode along onto the live preview (and into the
capture).

- AdjustPanel: CANCEL chip next to ACCEPT. It drops the un-accepted draft
  and restores the last ACCEPTED mark (none if nothing was accepted).
- Viewfinder: draws the mark whenever the chip is ON with text, but only
  lets it CAPTURE touches while its editor is open (new wmEditing prop).
  A double-tap ON the mark still re-opens that editor from the library
  viewer.
- App: ACCEPT and CANCEL now close the editor (that closes the placement
  layer with it). Switching mode closes the deck panels, and leaves the
  frame behind: camera mode has no FRAME picker to undo one.

Verified on device (9a6a7277): camera tap locks AE/AF with the watermark
left ON; library polaroid no longer appears on the live preview after the
switch; CANCEL reverts the chip to CUSTOM WATERMARK OFF and closes the
panel; ACCEPT closes it and the next capture embeds the mark (amber text
found at 0.5/0.375 of the 3000x4000 export), while a capture before
ACCEPT carries none.

App.tsx

@@ -97,6 +97,26 @@ export default function App() {
     setCustomWm(wm);
     if (!wm.enabled) setCustomWmApplied({ ...DEFAULT_CUSTOM_WM });
   };
+  // Leaving the watermark editor = closing its panel. The mark keeps capturing
+  // image touches ONLY while that panel is open (Viewfinder's wmArmed), so this
+  // is what hands the photo back to tap-to-focus / pinch / double-tap zoom.
+  const closeWatermarkEditor = () => {
+    setOpenTab(null);
+    setOpenParamKey(null);
+  };
+  // ACCEPT: the draft becomes the mark the export burns in, then the editor
+  // closes so the image stops being a placement surface.
+  const handleAcceptCustomWm = () => {
+    setCustomWmApplied({ ...customWm });
+    closeWatermarkEditor();
+  };
+  // CANCEL: drop every un-accepted edit and fall back to the last ACCEPTED mark
+  // (none at all when nothing was ever accepted), then close exactly like
+  // ACCEPT — the escape hatch a running session previously lacked.
+  const handleCancelCustomWm = () => {
+    setCustomWm({ ...customWmApplied });
+    closeWatermarkEditor();
+  };
   // Composition aspect-ratio (FULL / 4:3 / 3:2 upright) + RAW DNG sidecar.
   const [aspectRatio, setAspectRatio] = useState<AspectRatio>('full');
   const [rawEnabled, setRawEnabled] = useState(false);
@@ -816,15 +836,20 @@ export default function App() {
   // Switching back to camera: drop GPS that belongs to a library photo, so the
   // live view (and any capture) never stamps a stale location.
   const handleSetMode = (next: 'camera' | 'library') => {
+    if (next === mode) return;
     if (next === 'camera' && gpsInfo && gpsInfo.source !== 'device') {
       setGpsInfo(null);
     }
-    // FRAME only exists in library mode — close the panel when switching back
-    // to camera so a dead frame chip row never lingers over the live preview.
-    if (next === 'camera' && openTab === 'frame') {
-      setOpenTab(null);
-      setOpenParamKey(null);
-    }
+    // The deck panels belong to one mode only (FRAME exists in library alone,
+    // and the WATERMARK panel is the watermark's edit session), so every switch
+    // closes them: no frame chip row over the live preview, and no watermark
+    // placement layer left eating the camera's tap-to-focus.
+    setOpenTab(null);
+    setOpenParamKey(null);
+    // A frame was picked for the still it sits on; camera mode has no FRAME
+    // picker to undo it, so it must never follow the user onto the live camera
+    // (and into the capture, which burns the frame in).
+    if (next === 'camera') setSelectedFrame('none');
     setMode(next);
   };
 
@@ -975,8 +1000,17 @@ export default function App() {
           meteringAdjustments={meteringAdj}
           imageAdjustTarget={imageAdjustTarget}
           customWm={customWm}
+          // The mark only captures image touches while its panel is open, so a
+          // watermark left ON cannot block tap-to-focus or pinch/zoom.
+          wmEditing={openTab === 'watermark'}
           onWmPositionChange={(x, y) => setCustomWm((p) => ({ ...p, x, y }))}
-          onWmEdit={() => setWmEditNonce((n) => n + 1)}
+          onWmEdit={() => {
+            // Double-tap on the mark re-opens its editor (and with it the
+            // placement layer), then focuses the input.
+            setOpenTab('watermark');
+            setOpenParamKey(null);
+            setWmEditNonce((n) => n + 1);
+          }}
         />
       </View>
 
@@ -1019,7 +1053,8 @@ export default function App() {
               onDeleteRecipe={handleDeleteRecipe}
               customWm={customWm}
               onUpdateCustomWm={handleUpdateCustomWm}
-              onAcceptCustomWm={() => setCustomWmApplied({ ...customWm })}
+              onAcceptCustomWm={handleAcceptCustomWm}
+              onCancelCustomWm={handleCancelCustomWm}
               wmEditNonce={wmEditNonce}
             />
           </View>