feat: Implement My Courses page with course cards, filtering, and certificate download functionality.

Frontend-Learner/components/course/CourseCard.vue

@@ -37,6 +37,8 @@ interface CourseCardProps {
   showStudyAgain?: boolean
   /** URL for course thumbnail image */
   image?: string
+  /** Loading state for actions */
+  loading?: boolean
 }
 
 const props = defineProps<CourseCardProps>()
@@ -156,6 +158,7 @@ const displayDescription = computed(() => getLocalizedText(props.description))
             class="w-full font-black shadow-lg shadow-emerald-600/20"
             style="background: linear-gradient(135deg, #10b981 0%, #059669 100%); color: white;"
             :label="$t('course.downloadCertificate')"
+            :loading="loading"
             @click="emit('viewCertificate')"
         />
       </div>