chore: extract performance singleton to separate file (#119)

Author: oblador

packages/react-native-performance/src/index.ts

@@ -1,5 +1,4 @@
 import { NativeEventEmitter, NativeModules, Platform } from 'react-native';
-import { createPerformance } from './performance';
 import {
   PerformanceReactNativeMark,
   PerformanceMetric,
@@ -8,7 +7,7 @@ import {
   installResourceLogger,
   uninstallResourceLogger,
 } from './resource-logger';
-const { PerformanceObserver, addEntry, performance } = createPerformance();
+import { PerformanceObserver, addEntry, performance } from './instance';
 
 declare const global: { __turboModuleProxy: null | {} };
 

packages/react-native-performance/src/instance.ts

@@ -0,0 +1,3 @@
+import { createPerformance } from './performance';
+export const { PerformanceObserver, addEntry, performance } =
+  createPerformance();