CSCEXAM-1159 Move Collab search to Regular search as a tab

- Consolidate collaborative exam search into the main exam search component.
- Introduce tab navigation for regular and collaborative exams.
- Remove deprecated collaborative exam search component.
- Update routing to reflect changes in exam search structure.
- Enhance loading and error handling for exam searches.

Author: VirmasaloA

ui/src/app/app.routes.ts

@@ -84,14 +84,6 @@ export const APP_ROUTES: Route[] = [
         loadComponent: () => import('./enrolment/search/exam-search.component').then((mod) => mod.ExamSearchComponent),
         title: () => buildTitle('i18n_exams_title'),
     },
-    {
-        path: 'exams/collaborative',
-        loadComponent: () =>
-            import('./enrolment/search/collaborative-exam-search.component').then(
-                (mod) => mod.CollaborativeExamSearchComponent,
-            ),
-        title: () => buildTitle('i18n_collaborative_exams_title'),
-    },
     {
         path: 'participations',
         loadComponent: () =>