refactor: break up vault services (#2364)

packages/services/src/Domain/VaultUser/UseCase/IsVaultAdmin.ts

@@ -0,0 +1,12 @@
+import { Result, SyncUseCaseInterface } from '@standardnotes/domain-core'
+import { SharedVaultListingInterface } from '@standardnotes/models'
+
+export class IsVaultAdmin implements SyncUseCaseInterface<boolean> {
+  execute(dto: { sharedVault: SharedVaultListingInterface; userUuid: string }): Result<boolean> {
+    if (!dto.sharedVault.sharing.ownerUserUuid) {
+      throw new Error(`Shared vault ${dto.sharedVault.sharing.sharedVaultUuid} does not have an owner user uuid`)
+    }
+
+    return Result.ok(dto.sharedVault.sharing.ownerUserUuid === dto.userUuid)
+  }
+}