Add iOS privacy purpose strings and version display

- Add descriptive purpose strings for camera, photo library, and microphone
- Display app version and build number on profile screen
- Add email redirect URL for sign-up flow
- Update Android OAuth client configurations

🤖 Generated with [Claude Code](https://claude.com/claude-code)

apps/mobile/app/(auth)/login.tsx

@@ -228,6 +228,9 @@ export default function LoginScreen() {
             const { data, error: signUpError } = await supabase.auth.signUp({
                 email: email.trim(),
                 password,
+                options: {
+                    emailRedirectTo: Linking.createURL("/(auth)/login"),
+                },
             });
 
             setIsLoading(false);