docs: add Skills tutorial video and update embedded video on skills page (#538)

Co-authored-by: Sannidhya <sann@Sannidhyas-MacBook-Pro.local>

Author: SannidhyaSah

docs/features/skills.mdx

@@ -15,7 +15,7 @@ Skills package task-specific instructions that Roo loads on-demand when your req
 
 <div style={{ position: 'relative', paddingBottom: '56.25%', height: 0, overflow: 'hidden' }}>
   <iframe
-    src="https://www.youtube.com/embed/cK2CBU54bhw?rel=0&modestbranding=1"
+    src="https://www.youtube.com/embed/1992Rpfc800?rel=0&modestbranding=1"
     style={{
       position: 'absolute',
       top: 0,

docs/tutorial-videos.json

@@ -63,6 +63,10 @@
     {
       "id": "BRrhcYYSh9M",
       "title": "Worktrees"
+    },
+    {
+      "id": "1992Rpfc800",
+      "title": "Skills"
     }
   ]
 }