Fix prefix URL routing to handle CIDR notation with slashes

- Use wildcard route pattern for /prefix/* endpoints
- Extract prefix parameter using chi.URLParam(r, "*")
- Fixes 400 error when accessing /prefix/x.x.x.x/32 directly

internal/metrics/metrics.go

@@ -30,6 +30,14 @@ type Tracker struct {
 	// Route update metrics
 	ipv4UpdateRate metrics.Meter
 	ipv6UpdateRate metrics.Meter
+
+	// Announcement/withdrawal metrics
+	announcementCounter metrics.Counter
+	withdrawalCounter   metrics.Counter
+	churnRate           metrics.Meter // combined announcements + withdrawals per second
+
+	// BGP peer tracking
+	bgpPeerCount atomic.Int32
 }
 
 // New creates a new metrics tracker
@@ -37,15 +45,18 @@ func New() *Tracker {
 	registry := metrics.NewRegistry()
 
 	return &Tracker{
-		registry:        registry,
-		messageCounter:  metrics.NewCounter(),
-		byteCounter:     metrics.NewCounter(),
-		messageRate:     metrics.NewMeter(),
-		byteRate:        metrics.NewMeter(),
-		wireByteCounter: metrics.NewCounter(),
-		wireByteRate:    metrics.NewMeter(),
-		ipv4UpdateRate:  metrics.NewMeter(),
-		ipv6UpdateRate:  metrics.NewMeter(),
+		registry:            registry,
+		messageCounter:      metrics.NewCounter(),
+		byteCounter:         metrics.NewCounter(),
+		messageRate:         metrics.NewMeter(),
+		byteRate:            metrics.NewMeter(),
+		wireByteCounter:     metrics.NewCounter(),
+		wireByteRate:        metrics.NewMeter(),
+		ipv4UpdateRate:      metrics.NewMeter(),
+		ipv6UpdateRate:      metrics.NewMeter(),
+		announcementCounter: metrics.NewCounter(),
+		withdrawalCounter:   metrics.NewCounter(),
+		churnRate:           metrics.NewMeter(),
 	}
 }
 
@@ -134,6 +145,56 @@ func (t *Tracker) RecordIPv6Update() {
 	t.ipv6UpdateRate.Mark(1)
 }
 
+// RecordAnnouncement records a route announcement
+func (t *Tracker) RecordAnnouncement() {
+	t.announcementCounter.Inc(1)
+	t.churnRate.Mark(1)
+}
+
+// RecordWithdrawal records a route withdrawal
+func (t *Tracker) RecordWithdrawal() {
+	t.withdrawalCounter.Inc(1)
+	t.churnRate.Mark(1)
+}
+
+// SetBGPPeerCount updates the current BGP peer count
+func (t *Tracker) SetBGPPeerCount(count int) {
+	// BGP peer count is always small (< 1000), so int32 is safe
+	if count > 0 && count < 1<<31 {
+		t.bgpPeerCount.Store(int32(count)) //nolint:gosec // count is validated
+	}
+}
+
+// GetBGPPeerCount returns the current BGP peer count
+func (t *Tracker) GetBGPPeerCount() int {
+	return int(t.bgpPeerCount.Load())
+}
+
+// GetAnnouncementCount returns the total announcement count
+func (t *Tracker) GetAnnouncementCount() uint64 {
+	count := t.announcementCounter.Count()
+	if count < 0 {
+		return 0
+	}
+
+	return uint64(count)
+}
+
+// GetWithdrawalCount returns the total withdrawal count
+func (t *Tracker) GetWithdrawalCount() uint64 {
+	count := t.withdrawalCounter.Count()
+	if count < 0 {
+		return 0
+	}
+
+	return uint64(count)
+}
+
+// GetChurnRate returns the route churn rate per second
+func (t *Tracker) GetChurnRate() float64 {
+	return t.churnRate.Rate1()
+}
+
 // GetRouteMetrics returns current route update metrics
 func (t *Tracker) GetRouteMetrics() RouteMetrics {
 	return RouteMetrics{