[PM-24677] Slim StateService down so it can be moved to state lib (#16021)

* Slim StateService down so it can be moved to state lib

* Fix accidental import changes

* Add `switchAccount` assertion

* Needs to use mock

libs/key-management/src/key.service.ts

@@ -732,7 +732,7 @@ export class DefaultKeyService implements KeyServiceAbstraction {
 
   protected async getKeyFromStorage(
     keySuffix: KeySuffixOptions,
-    userId?: UserId,
+    userId: UserId,
   ): Promise<UserKey | null> {
     if (keySuffix === KeySuffixOptions.Auto) {
       const userKey = await this.stateService.getUserKeyAutoUnlock({ userId: userId });