Add guard for empty organization

Author: LauraBeatris

.changeset/petite-ravens-see.md

@@ -0,0 +1,5 @@
+---
+'@clerk/clerk-js': patch
+---
+
+Do not allow `setActive({ organization: null })` when organization selection is forced

packages/clerk-js/src/core/clerk.ts

@@ -1071,6 +1071,10 @@ export class Clerk implements ClerkInterface {
         );
       }
 
+      if (!organization && this.environment?.organizationSettings.forceOrganizationSelection) {
+        throw new Error('setActive requires an organization parameter when organization selection is forced.');
+      }
+
       const onBeforeSetActive: SetActiveHook =
         typeof window !== 'undefined' && typeof window.__unstable__onBeforeSetActive === 'function'
           ? window.__unstable__onBeforeSetActive