Add status page enhancements with new metrics and footer

- Add GC statistics (run count, total/last pause, heap usage)
- Add BGP peer count tracking from RIS Live OPEN/NOTIFICATION messages
- Add route churn rate metric (announcements + withdrawals per second)
- Add announcement and withdrawal counters
- Add footer with attribution, license, and git revision
- Embed git revision at build time via ldflags
- Update HTML template to display all new metrics

internal/server/handlers.go

@@ -469,6 +469,25 @@ func (s *Server) handleStats() http.HandlerFunc {
 			connectionDuration = time.Since(metrics.ConnectedSince).Truncate(time.Second).String()
 		}
 
+		// Get announcement/withdrawal stats from metrics tracker
+		metricsTracker := s.streamer.GetMetricsTracker()
+		announcements := metricsTracker.GetAnnouncementCount()
+		withdrawals := metricsTracker.GetWithdrawalCount()
+		churnRate := metricsTracker.GetChurnRate()
+		bgpPeerCount := metricsTracker.GetBGPPeerCount()
+
+		// Calculate last GC pause
+		const (
+			nanosecondsPerMillisecond = 1e6
+			gcPauseHistorySize        = 256 // Size of runtime.MemStats.PauseNs circular buffer
+		)
+		var lastPauseMs float64
+		if memStats.NumGC > 0 {
+			// PauseNs is a circular buffer, get the most recent pause
+			lastPauseIdx := (memStats.NumGC + gcPauseHistorySize - 1) % gcPauseHistorySize
+			lastPauseMs = float64(memStats.PauseNs[lastPauseIdx]) / nanosecondsPerMillisecond
+		}
+
 		stats := StatsResponse{
 			Uptime:                 uptime,
 			TotalMessages:          metrics.TotalMessages,
@@ -483,6 +502,19 @@ func (s *Server) handleStats() http.HandlerFunc {
 			GoVersion:              runtime.Version(),
 			Goroutines:             runtime.NumGoroutine(),
 			MemoryUsage:            humanize.Bytes(memStats.Alloc),
+			GC: GCStats{
+				NumGC:          memStats.NumGC,
+				TotalPauseMs:   memStats.PauseTotalNs / uint64(nanosecondsPerMillisecond),
+				LastPauseMs:    lastPauseMs,
+				HeapAllocBytes: memStats.HeapAlloc,
+				HeapSysBytes:   memStats.HeapSys,
+			},
+			Stream: StreamStats{
+				Announcements:    announcements,
+				Withdrawals:      withdrawals,
+				RouteChurnPerSec: churnRate,
+				BGPPeerCount:     bgpPeerCount,
+			},
 			ASNs:                   dbStats.ASNs,
 			Prefixes:               dbStats.Prefixes,
 			IPv4Prefixes:           dbStats.IPv4Prefixes,