Fix deadlock in snapshotter and add timing logs

- Move GetDetailedStats() call outside of read lock to avoid deadlock
- Add timing logs to identify performance bottlenecks during snapshot
- Log duration for copying routes, marshaling JSON, and writing to disk

internal/snapshotter/snapshotter.go

@@ -138,11 +138,18 @@ func (s *Snapshotter) TakeSnapshot() error {
 	s.logger.Info("Starting routing table snapshot")
 
 	// Get a copy of all routes while holding read lock
+	copyStart := time.Now()
 	s.rt.RLock()
 	routes := s.rt.GetAllRoutesUnsafe() // We'll need to add this method
-	stats := s.rt.GetDetailedStats()
 	s.rt.RUnlock()
 
+	// Get stats separately to avoid deadlock
+	stats := s.rt.GetDetailedStats()
+
+	s.logger.Info("Copied routes from routing table",
+		"duration", time.Since(copyStart),
+		"route_count", len(routes))
+
 	// Create snapshot data structure
 	snapshot := struct {
 		Timestamp time.Time                  `json:"timestamp"`
@@ -155,10 +162,14 @@ func (s *Snapshotter) TakeSnapshot() error {
 	}
 
 	// Serialize to JSON
+	marshalStart := time.Now()
 	jsonData, err := json.Marshal(snapshot)
 	if err != nil {
 		return fmt.Errorf("failed to marshal snapshot: %w", err)
 	}
+	s.logger.Info("Marshaled snapshot to JSON",
+		"duration", time.Since(marshalStart),
+		"size_bytes", len(jsonData))
 
 	// Write compressed data to temporary file
 	tempPath := filepath.Join(s.stateDir, snapshotFilename+tempFileSuffix)
@@ -183,6 +194,7 @@ func (s *Snapshotter) TakeSnapshot() error {
 	gzipWriter.Comment = fmt.Sprintf("RouteWatch snapshot taken at %s", snapshot.Timestamp.Format(time.RFC3339))
 
 	// Write compressed data
+	writeStart := time.Now()
 	if _, err := gzipWriter.Write(jsonData); err != nil {
 		return fmt.Errorf("failed to write compressed data: %w", err)
 	}
@@ -206,6 +218,8 @@ func (s *Snapshotter) TakeSnapshot() error {
 	if err := os.Rename(tempPath, finalPath); err != nil {
 		return fmt.Errorf("failed to rename temporary file: %w", err)
 	}
+	s.logger.Info("Wrote compressed snapshot to disk",
+		"duration", time.Since(writeStart))
 
 	duration := time.Since(start)
 	s.lastSnapshot = time.Now()