chore(nextjs-insights): remove feature flag registration (#95543)

Author: shellmayr

src/sentry/features/temporary.py

@@ -189,8 +189,6 @@ def register_temporary_features(manager: FeatureManager):
     manager.add("organizations:navigation-sidebar-v2", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=True)
     manager.add("organizations:navigation-sidebar-v2-banner", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=True)
     manager.add("organizations:new-page-filter", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, default=True, api_expose=True)
-    # Enable access to NextJS specific insights
-    manager.add("organizations:nextjs-insights", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=True)
     # Enable AI Agents specific insights
     manager.add("organizations:agents-insights", OrganizationFeature, FeatureHandlerStrategy.FLAGPOLE, api_expose=True)
     # Enable MCP specific insights