feat: improve LMS course discovery and enrollment UX

- Add paginated recommended courses to LMS dashboard (top 3, list
    view)
    and explore page (12 per page); exclude courses blocking new
    students
  - Polish course preview modal: remove padding, render requirements as
    HTML, round banner image, secondary close button
  - Redirect to course start page after successful enrollment instead of
    /lms;
    keep spinner active until navigation completes
  - Auto-enable "allow new students" when a course is published
  - Move Explore after My Learning in LMS sidebar nav
  - Move Certificates after Content in course sidebar
  - Add hiddenColumns prop to CourseListRow; show "Learn more" button
    instead of actions menu in LMS explore context

apps/dashboard/src/lib/features/ui/navigation/lms-navigation.ts

@@ -57,6 +57,12 @@ export const baseNavConfig: NavItemConfig[] = [
     icon: CourseIcon,
     matchPattern: '^/lms/mylearning(/.*)?$'
   },
+  {
+    titleKey: 'lms_navigation.explore',
+    path: '/explore',
+    icon: ExploreIcon,
+    matchPattern: '^/lms/explore(/.*)?$'
+  },
   {
     titleKey: 'lms_navigation.programs',
     path: '/programs',
@@ -76,20 +82,14 @@ export const baseNavConfig: NavItemConfig[] = [
     icon: CommunityIcon,
     matchPattern: '^/lms/community(/.*)?$',
     show: (currentOrg) => currentOrg?.customization?.dashboard?.community === true,
-    supportsDynamicSegment: true, // Supports /community/[slug]
+    supportsDynamicSegment: true,
     nestedRoutes: [
       {
         path: 'ask',
-        titleKey: 'Ask Question' // Could be translated
+        titleKey: 'Ask Question'
       }
     ]
   },
-  {
-    titleKey: 'lms_navigation.explore',
-    path: '/explore',
-    icon: ExploreIcon,
-    matchPattern: '^/lms/explore(/.*)?$'
-  },
   {
     titleKey: 'lms_navigation.settings',
     path: '/settings',