fix(server): don't publicly reveal user count (#4409)

* fix: don't reveal user count publicly

* fix: mobile and user controller

* fix: update other frontend endpoints

* fix: revert openapi change

* chore: open api

* fix: initialize

* openapi

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Co-authored-by: Alex Tran <alex.tran1502@gmail.com>

server/src/domain/repositories/user.repository.ts

@@ -18,6 +18,7 @@ export const IUserRepository = 'IUserRepository';
 export interface IUserRepository {
   get(id: string, withDeleted?: boolean): Promise<UserEntity | null>;
   getAdmin(): Promise<UserEntity | null>;
+  hasAdmin(): Promise<boolean>;
   getByEmail(email: string, withPassword?: boolean): Promise<UserEntity | null>;
   getByStorageLabel(storageLabel: string): Promise<UserEntity | null>;
   getByOAuthId(oauthId: string): Promise<UserEntity | null>;