Upgrade to Expo SDK 57 (#44)

With Xcode 27, `npx expo run:ios` fails on Expo SDK 54 before it even
looks at devices: Xcode 27 replaced Simulator.app with DeviceHub.app, and
the SDK 54 CLI still checks for Simulator.app. The fix is only in the
SDK 56+ CLI, so move the sample to SDK 57.

- expo 54 -> 57, react-native 0.81.5 -> 0.86.3, react 19.2.3, and all
  Expo-managed packages aligned with `npx expo install --fix`
- @config-plugins/react-native-webrtc 13 -> 15 (supports SDK 56+)
- @livekit/react-native-expo-plugin 1.0.1 -> 1.0.3 (fixes the
  config-plugins import that broke on SDK 57)
- typescript 6.0 as a dev dependency only; drop the stray runtime entry
- CI on Node 22, required by react-native 0.86 and Metro
- useThemeColor: ColorSchemeName now includes 'unspecified'; treat
  everything except 'dark' as light
- ControlBar: derive the track reference with useMemo instead of
  setState inside an effect (new react-hooks lint rule)

Co-authored-by: Claude Fable 5.1 <noreply@anthropic.com>

Author: MaxHeimbrock

.github/workflows/test.yaml

@@ -17,7 +17,7 @@ jobs:
 
       - uses: actions/setup-node@v6
         with:
-          node-version: '18.x'
+          node-version: '22.x'
 
       - uses: actions/cache@v5
         with:

app/assistant/ui/ControlBar.tsx

@@ -1,6 +1,6 @@
 import { TrackReference, useLocalParticipant } from '@livekit/components-react';
 import { BarVisualizer } from '@livekit/react-native';
-import { useEffect, useState } from 'react';
+import { useMemo } from 'react';
 import {
   ViewStyle,
   StyleSheet,
@@ -29,22 +29,18 @@ type ControlBarOptions = {
 
 export default function ControlBar({ style = {}, options }: ControlBarProps) {
   const { microphoneTrack, localParticipant } = useLocalParticipant();
-  const [trackRef, setTrackRef] = useState<TrackReference | undefined>(
-    undefined
+  const trackRef = useMemo<TrackReference | undefined>(
+    () =>
+      microphoneTrack
+        ? {
+            participant: localParticipant,
+            publication: microphoneTrack,
+            source: microphoneTrack.source,
+          }
+        : undefined,
+    [microphoneTrack, localParticipant]
   );
 
-  useEffect(() => {
-    if (microphoneTrack) {
-      setTrackRef({
-        participant: localParticipant,
-        publication: microphoneTrack,
-        source: microphoneTrack.source,
-      });
-    } else {
-      setTrackRef(undefined);
-    }
-  }, [microphoneTrack, localParticipant]);
-
   // Images
   let micImage = options.isMicEnabled
     ? require('@/assets/images/mic_24dp.png')

hooks/useThemeColor.ts

@@ -10,7 +10,8 @@ export function useThemeColor(
   props: { light?: string; dark?: string },
   colorName: keyof typeof Colors.light & keyof typeof Colors.dark
 ) {
-  const theme = useColorScheme() ?? 'light';
+  // ColorSchemeName can also be null or 'unspecified'; treat everything but 'dark' as light.
+  const theme = useColorScheme() === 'dark' ? 'dark' : 'light';
   const colorFromProps = props[theme];
 
   if (colorFromProps) {