fix(mobile): use a proper pull request icon on iOS

apps/mobile/src/components/AppSymbol.ios.tsx

@@ -1,3 +1,4 @@
+import IconGitPullRequest from "@tabler/icons-react-native/IconGitPullRequest";
 import { SymbolView as ExpoSymbolView } from "expo-symbols";
 import { withUniwind } from "uniwind";
 import type { AppSymbolViewProps } from "./AppSymbol";
@@ -6,10 +7,24 @@ export type { SFSymbol } from "expo-symbols";
 export type { AppSymbolName } from "./AppSymbol";
 
 /**
- * Keep the iOS implementation isolated from the Android Tabler fallback so
- * Metro does not initialize the icon package when iOS renders SF Symbols.
+ * Use SF Symbols on iOS except for pull requests, which have no matching
+ * native glyph. Import only that Tabler icon to keep the bundle small.
  */
 function AppSymbolView(props: AppSymbolViewProps) {
+  const name = typeof props.name === "string" ? props.name : props.name.ios;
+  if (name === "arrow.triangle.pull") {
+    return (
+      <IconGitPullRequest
+        accessibilityLabel={props.accessibilityLabel}
+        color={props.tintColor}
+        size={props.size}
+        strokeWidth={2}
+        style={props.style}
+        testID={props.testID}
+      />
+    );
+  }
+
   return <ExpoSymbolView {...props} />;
 }