feat(flags): export FeatureFlagContext type from core/types-hoist

Author: aliu39

packages/core/src/types-hoist/index.ts

@@ -19,6 +19,7 @@ export type {
   TraceContext,
   CloudResourceContext,
   MissingInstrumentationContext,
+  FeatureFlagContext,
 } from './context';
 export type { DataCategory } from './datacategory';
 export type { DsnComponents, DsnLike, DsnProtocol } from './dsn';