Remove RoutingTableHandler and snapshotter, use database for route stats

- Remove RoutingTableHandler as PrefixHandler maintains live_routes table
- Update server to get route counts from database instead of in-memory routing table
- Add GetLiveRouteCounts method to database for IPv4/IPv6 route counts
- Use metrics tracker in PrefixHandler for route update rates
- Remove snapshotter entirely as database contains all information
- Update tests to work without routing table

internal/database/database.go

@@ -522,3 +522,20 @@ func (d *Database) GetPrefixDistribution() (ipv4 []PrefixDistribution, ipv6 []Pr
 
 	return ipv4, ipv6, nil
 }
+
+// GetLiveRouteCounts returns the count of IPv4 and IPv6 routes
+func (d *Database) GetLiveRouteCounts() (ipv4Count, ipv6Count int, err error) {
+	// Get IPv4 count
+	err = d.db.QueryRow("SELECT COUNT(*) FROM live_routes WHERE ip_version = 4").Scan(&ipv4Count)
+	if err != nil {
+		return 0, 0, fmt.Errorf("failed to count IPv4 routes: %w", err)
+	}
+
+	// Get IPv6 count
+	err = d.db.QueryRow("SELECT COUNT(*) FROM live_routes WHERE ip_version = 6").Scan(&ipv6Count)
+	if err != nil {
+		return 0, 0, fmt.Errorf("failed to count IPv6 routes: %w", err)
+	}
+
+	return ipv4Count, ipv6Count, nil
+}