Optimize stats and TLD queries for performance

- Reduce stats loop interval from 1 minute to 10 seconds
- Simplify TLD query by removing expensive feeds JOIN (30s -> 1.8s)
- Sort TLDs alphabetically

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

crawler.go

@@ -68,11 +68,11 @@ func (c *Crawler) Close() error {
 	return nil
 }
 
-// StartStatsLoop updates cached stats once per minute
+// StartStatsLoop updates cached stats every 10 seconds
 func (c *Crawler) StartStatsLoop() {
 	for {
 		c.UpdateStats()
-		time.Sleep(1 * time.Minute)
+		time.Sleep(10 * time.Second)
 	}
 }