fix: Correct legacy rank detection - check rating range instead

The API returns CS:GO skill groups (0-18) in BOTH rank_old and rank_new
fields for legacy matches. Updated detection logic to:

- Check if rating (rank_new) is in 0-18 range (CS:GO skill groups)
- CS2 ratings are typically 1000-30000, so no overlap
- Use rating value for RankIcon display (contains current skill group)

Debug output showed:
- rating: 15-17 (CS:GO skill groups)
- oldRating: same values (15-17)
- Previous logic failed because rating was not 0

This fix properly detects and displays CS:GO rank icons for legacy matches.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/lib/components/ui/PremierRatingBadge.svelte

@@ -23,14 +23,15 @@
 		class: className = ''
 	}: Props = $props();
 
-	// Determine if this is a legacy CS:GO match (has old rank but no new rating)
-	// CS:GO skill groups are 0-18, CS2 ratings are typically > 1000
+	// Determine if this is a legacy CS:GO match
+	// CS:GO skill groups are 0-18, CS2 ratings are typically 1000-30000
+	// For legacy matches, both rating and oldRating will be in the 0-18 range
 	const isLegacyRank = $derived(
-		oldRating !== undefined &&
-			oldRating !== null &&
-			oldRating >= 0 &&
-			oldRating <= 18 &&
-			(!rating || rating === 0 || rating > 30000)
+		rating !== undefined &&
+			rating !== null &&
+			rating >= 0 &&
+			rating <= 18 &&
+			(oldRating === undefined || oldRating === null || (oldRating >= 0 && oldRating <= 18))
 	);
 
 	// Debug logging (temporary)
@@ -68,7 +69,8 @@
 
 {#if isLegacyRank}
 	<!-- Show CS:GO rank icon for legacy matches -->
-	<RankIcon skillGroup={oldRating} {size} class={className} />
+	<!-- Use rating (rank_new) as it contains the current skill group -->
+	<RankIcon skillGroup={rating} {size} class={className} />
 {:else if !rating || rating === 0}
 	<!-- No rating available -->
 	<span class="text-sm text-base-content/50">Unranked</span>