feat(editor): Show avatars for users currently working on the same workflow (#7763)

This PR introduces the following changes:
- New Vue stores: `collaborationStore` and `pushConnectionStore`
- Front-end push connection handling overhaul: Keep only a singe
connection open and handle it from the new store
- Add user avatars in the editor header when there are multiple users
working on the same workflow
- Sending a heartbeat event to back-end service periodically to confirm
user is still active

- Back-end overhauls (authored by @tomi):
  - Implementing a cleanup procedure that removes inactive users
  - Refactoring collaboration service current implementation

---------

Co-authored-by: Tomi Turtiainen <10324676+tomi@users.noreply.github.com>

packages/editor-ui/src/Interface.ts

@@ -411,6 +411,16 @@ export interface IExecutionDeleteFilter {
 	ids?: string[];
 }
 
+export type PushDataUsersForWorkflow = {
+	workflowId: string;
+	activeUsers: Array<{ user: IUser; lastSeen: string }>;
+};
+
+type PushDataWorkflowUsersChanged = {
+	data: PushDataUsersForWorkflow;
+	type: 'activeWorkflowUsersChanged';
+};
+
 export type IPushData =
 	| PushDataExecutionFinished
 	| PushDataExecutionStarted
@@ -424,7 +434,8 @@ export type IPushData =
 	| PushDataWorkerStatusMessage
 	| PushDataActiveWorkflowAdded
 	| PushDataActiveWorkflowRemoved
-	| PushDataWorkflowFailedToActivate;
+	| PushDataWorkflowFailedToActivate
+	| PushDataWorkflowUsersChanged;
 
 type PushDataActiveWorkflowAdded = {
 	data: IActiveWorkflowAdded;
@@ -690,6 +701,7 @@ export interface IUser extends IUserResponse {
 	fullName?: string;
 	createdAt?: string;
 	mfaEnabled: boolean;
+	globalRoleId?: number;
 }
 
 export interface IVersionNotificationSettings {