fix(app): restore mobile left sidebar swipe (#1976)

Keep the shared sidebar model outside the root gesture detector so Gesture Handler attaches to the native surface on Android/Fabric.

docs/mobile-panels.md

@@ -70,6 +70,9 @@ definition, no longer eligible to begin.
 
 - Callers request semantic targets through `panel-store`; they never write shared values.
 - Gesture behavior comes from the four explicit hooks in `mobile-panels/gestures.ts`.
+- Keep `SidebarModelProvider` outside `MobileGestureWrapper`. The provider shares sidebar derivation
+  across consumers, while Gesture Handler requires the wrapper's direct child to be a native `View`
+  so its injected `collapsable={false}` reaches Android/Fabric.
 - Mobile sidebars render through `MobilePanelOverlay`; do not duplicate overlay lifecycle or motion
   styles in sidebar components.
 - Animated panel nodes use React Native static styles plus inline theme values. Do not attach

packages/app/src/app/_layout.tsx

@@ -464,8 +464,7 @@ function AppContainer({ children, chromeEnabled: chromeEnabledOverride }: AppCon
     </View>
   );
 
-  const content = (
-    <SidebarModelProvider>
+  const surface = (
     <View style={layoutStyles.surfaceFill}>
       {workspaceChrome}
       <FloatingPanelPortalHost />
@@ -483,14 +482,15 @@ function AppContainer({ children, chromeEnabled: chromeEnabledOverride }: AppCon
       <KeyboardShortcutsDialog />
       <QuittingOverlay />
     </View>
-    </SidebarModelProvider>
   );
 
-  if (!isCompactLayout) {
-    return content;
-  }
+  const content = isCompactLayout ? (
+    <MobileGestureWrapper chromeEnabled={chromeEnabled}>{surface}</MobileGestureWrapper>
+  ) : (
+    surface
+  );
 
-  return <MobileGestureWrapper chromeEnabled={chromeEnabled}>{content}</MobileGestureWrapper>;
+  return <SidebarModelProvider>{content}</SidebarModelProvider>;
 }
 
 function MobileGestureWrapper({