fix: Robust parsing of SIP messages from tcpdump output containing raw header artifacts

internal/capture/local.go

@@ -139,8 +139,11 @@ func (c *LocalCapturer) processStream(r io.Reader) {
 		// logger.Debug("Stdout: %s", line) // Commented out to reduce noise, enable if needed
 
 		// Detect start of SIP message
-		if isSIPStart(line) {
+		if idx := findSIPStart(line); idx != -1 {
 			logger.Debug("SIP Start detected: %s", line)
+			// Clean the line (remove prefix garbage)
+			line = line[idx:]
+
 			// If we were building a message, parse it
 			if buffer.Len() > 0 {
 				c.parseAndEmit(buffer.String())