refactor(core): Abstract away InstanceSettings and encryptionKey into injectable services (no-changelog) (#7471)

This change ensures that things like `encryptionKey` and `instanceId`
are always available directly where they are needed, instead of passing
them around throughout the code.

packages/core/src/Interfaces.ts

@@ -15,12 +15,6 @@ export interface IResponseError extends Error {
 	statusCode?: number;
 }
 
-export interface IUserSettings {
-	encryptionKey?: string;
-	tunnelSubdomain?: string;
-	instanceId?: string;
-}
-
 export interface IWorkflowSettings extends IWorkflowSettingsWorkflow {
 	errorWorkflow?: string;
 	timezone?: string;