docs(apple, android): Enable standalone app start tracing in getting started guides

docs/platforms/android/index.mdx

@@ -122,6 +122,8 @@ Configuration is done via the application `AndroidManifest.xml`. Here's an examp
   <!-- ___PRODUCT_OPTION_START___ performance -->
   <!-- Enable the performance API by setting a sample-rate, adjust in production env -->
   <meta-data android:name="io.sentry.traces.sample-rate" android:value="1.0" />
+  <!-- Send app start data as a standalone transaction for more accurate measurements -->
+  <meta-data android:name="io.sentry.standalone-app-start-tracing.enable" android:value="true" />
   <!-- ___PRODUCT_OPTION_END___ performance -->
   <!-- ___PRODUCT_OPTION_START___ profiling -->
   <!-- Enable profiling, adjust in production env. This is evaluated only once per session -->

includes/apple-platform-getting-started.mdx

@@ -111,6 +111,9 @@ func application(_ application: UIApplication,
         // Set tracesSampleRate to 1 to capture 100% of transactions for performance monitoring.
         // We recommend adjusting this value in production.
         options.tracesSampleRate = 1
+
+        // Send app start data as a standalone transaction for more accurate measurements.
+        options.experimental.enableStandaloneAppStartTracing = true
         // ___PRODUCT_OPTION_END___ performance
         // ___PRODUCT_OPTION_START___ profiling
 
@@ -153,6 +156,9 @@ func application(_ application: UIApplication,
         // Set tracesSampleRate to 1.0 to capture 100% of transactions for performance monitoring.
         // We recommend adjusting this value in production.
         options.tracesSampleRate = @1.f;
+
+        // Send app start data as a standalone transaction for more accurate measurements.
+        options.experimental.enableStandaloneAppStartTracing = YES;
         // ___PRODUCT_OPTION_END___ performance
         // ___PRODUCT_OPTION_START___ profiling
 
@@ -196,6 +202,9 @@ struct SwiftUIApp: App {
             // Set tracesSampleRate to 1 to capture 100% of transactions for performance monitoring.
             // We recommend adjusting this value in production.
             options.tracesSampleRate = 1
+
+            // Send app start data as a standalone transaction for more accurate measurements.
+            options.experimental.enableStandaloneAppStartTracing = true
             // ___PRODUCT_OPTION_END___ performance
             // ___PRODUCT_OPTION_START___ profiling
 
@@ -240,6 +249,9 @@ func application(_ application: UIApplication,
         // Set tracesSampleRate to 1 to capture 100% of transactions for performance monitoring.
         // We recommend adjusting this value in production.
         options.tracesSampleRate = 1
+
+        // Send app start data as a standalone transaction for more accurate measurements.
+        options.experimental.enableStandaloneAppStartTracing = true
         // ___PRODUCT_OPTION_END___ performance
         // ___PRODUCT_OPTION_START___ profiling
 
@@ -276,6 +288,9 @@ func application(_ application: UIApplication,
         // Set tracesSampleRate to 1.0 to capture 100% of transactions for performance monitoring.
         // We recommend adjusting this value in production.
         options.tracesSampleRate = @1.f;
+
+        // Send app start data as a standalone transaction for more accurate measurements.
+        options.experimental.enableStandaloneAppStartTracing = YES;
         // ___PRODUCT_OPTION_END___ performance
 
         // ___PRODUCT_OPTION_START___ profiling
@@ -313,6 +328,9 @@ struct SwiftUIApp: App {
             // Set tracesSampleRate to 1 to capture 100% of transactions for performance monitoring.
             // We recommend adjusting this value in production.
             options.tracesSampleRate = 1
+
+            // Send app start data as a standalone transaction for more accurate measurements.
+            options.experimental.enableStandaloneAppStartTracing = true
             // ___PRODUCT_OPTION_END___ performance
             // ___PRODUCT_OPTION_START___ profiling