feat: implement video likes and play tracking UI

Video Detail Page (/videos/[slug]):
- Load like status from server on page load
- Add functional like button with heart icon
- Show likes count with real-time updates
- Track video plays when user clicks play
- Record watch progress every 10 seconds
- Mark video as completed at 90% watched
- Show toast notifications for like/unlike actions
- Require authentication to like videos

Video Listing Page (/videos):
- Display play count badge on video thumbnails
- Show play icon with count in top-right corner

Features:
- Like/unlike videos with live count updates
- Play tracking with analytics data
- Progress tracking for completion metrics
- Authentication-gated liking functionality
- User-friendly toast feedback

All UI components working and integrated with backend API

packages/frontend/src/routes/videos/+page.svelte

@@ -238,13 +238,15 @@ const filteredVideos = $derived(() => {
               </div>
             {/if}
 
-            <!-- Views -->
-            <!-- <div
-              class="absolute top-3 right-3 bg-black/70 text-white text-xs px-2 py-1 rounded-full flex items-center gap-1"
-            >
-              <EyeIcon class="w-3 h-3" />
-              {video.views}
-            </div> -->
+            <!-- Play Count -->
+            {#if video.plays_count}
+              <div
+                class="absolute top-3 right-3 bg-black/70 text-white text-xs px-2 py-1 rounded-full flex items-center gap-1"
+              >
+                <span class="icon-[ri--play-fill] w-3 h-3"></span>
+                {video.plays_count}
+              </div>
+            {/if}
 
             <!-- Play Overlay -->
             <a