Allow plugins to link into the WP bulk context menu

Currently, plugins cannot add context menu entries on work packages,
when more than one work package is selected.

This PR adds a plugin hook so that plugins can register for bulk actions.

frontend/src/app/features/plugins/plugin-context.ts

@@ -32,6 +32,7 @@ import { DomAutoscrollService } from 'core-app/shared/helpers/drag-and-drop/dom-
  */
 export class OpenProjectPluginContext {
   private _knownHookNames = [
+    'workPackageBulkContextMenu',
     'workPackageTableContextMenu',
     'workPackageSingleContextMenu',
     'workPackageNewInitialization',

frontend/src/app/features/work-packages/components/wp-table/context-menu-helper/wp-context-menu-helper.service.ts

@@ -103,13 +103,14 @@ export class WorkPackageContextMenuHelperService {
 
   public getIntersectOfPermittedActions(workPackages:any) {
     const bulkPermittedActions:any = [];
-
-    const permittedActions = _.filter(this.BULK_ACTIONS, (action:any) => _.every(workPackages, (workPackage:WorkPackageResource) => this.isActionAllowed(workPackage, action)));
+    const possibleActions = this.BULK_ACTIONS.concat(this.HookService.call('workPackageBulkContextMenu'));
+    const permittedActions = _.filter(possibleActions, (action:any) => _.every(workPackages, (workPackage:WorkPackageResource) => this.isActionAllowed(workPackage, action)));
 
     _.each(permittedActions, (permittedAction:any) => {
       bulkPermittedActions.push({
         key: permittedAction.key,
         text: permittedAction.text,
+        icon: permittedAction.icon,
         link: this.getBulkActionLink(permittedAction, workPackages),
       });
     });