React Native UI profiling docs (#16033)

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## DESCRIBE YOUR PR

This PR is to support changes in UI profiling for React Native done
here: getsentry/sentry-react-native#5518

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Author: alwx

docs/platforms/react-native/profiling/index.mdx

@@ -66,3 +66,30 @@ Sentry.init({
 #### platformProfilers
 
 Default value `true`, platform profilers are enabled. By default both React Native JS code executed in Hermes engine and platform specific code (Swift, Objective-C, Kotlin, Java) are profiled by their respective profilers. Setting `platformProfilers` to `false` will disable profiling of the platform specific code and only the JS code executed in Hermes will be profiled. This option is available since the SDK version [5.33.0](https://github.com/getsentry/sentry-react-native/releases/tag/5.33.0).
+
+## Android UI Profiling (experimental)
+
+<Alert>
+
+Profiling for React Native is available in SDK versions `7.9.0` and above. Android is currently the only supported platform, and support is still experimental.
+
+</Alert>
+
+```javascript
+import * as Sentry from '@sentry/react-native';
+
+Sentry.init({
+  dsn: 'YOUR_DSN',
+  tracesSampleRate: 1.0, // Required for trace mode
+
+  _experiments: {
+    androidProfilingOptions: {
+      profileSessionSampleRate: 1.0,
+      lifecycle: 'trace',
+      startOnAppStart: true,
+    },
+  },
+});
+```
+
+For more information, see [the Android SDK documentation](https://docs.sentry.io/platforms/android/profiling/#enabling-ui-profiling)