perf: reduce mobile video size

Improves upload and playback speed

js/mobile/src/features/compose/VideoRecordingOverlay.tsx

@@ -1,9 +1,10 @@
 import { useEffect, useRef, useState } from "react";
-import { Pressable, StyleSheet, Text, View } from "react-native";
+import { Platform, Pressable, StyleSheet, Text, View } from "react-native";
 import { CameraView } from "expo-camera";
 import { logError } from "@/lib/errors";
 
 const MAX_DURATION_S = 60;
+const VIDEO_BITRATE_BPS = 1_200_000;
 
 interface VideoRecordingOverlayProps {
   onComplete: (result: { uri: string; durationMs: number }) => void;
@@ -36,7 +37,10 @@ export function VideoRecordingOverlay({
 
     let result: { uri: string } | undefined;
     try {
-      result = await cam.recordAsync({ maxDuration: MAX_DURATION_S });
+      result = await cam.recordAsync({
+        maxDuration: MAX_DURATION_S,
+        ...(Platform.OS === "ios" ? { codec: "hvc1" as const } : {}),
+      });
     } catch (err) {
       if (cancelledRef.current) return;
       logError(err, { scope: "compose.video.recordAsync" });
@@ -83,6 +87,8 @@ export function VideoRecordingOverlay({
         ref={cameraRef}
         style={StyleSheet.absoluteFill}
         facing="front"
+        videoQuality="480p"
+        videoBitrate={VIDEO_BITRATE_BPS}
         mode="video"
         mute={false}
         onCameraReady={() => setCameraReady(true)}