refactor: move utility functions to printer module and fix formatting

- Move toMicroseconds and toMicrosecondsf helper functions from client.go to printer.go
- These functions are only used by the printer module for latency calculations
- Add missing newline at end of printer.go file

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: yuuki

client.go

@@ -306,14 +306,6 @@ func (c *Client) connectUDP(ctx context.Context, addrport string) error {
 	return eg.Wait()
 }
 
-func toMicroseconds(n int64) int64 {
-	return time.Duration(n).Microseconds()
-}
-
-func toMicrosecondsf(n float64) int64 {
-	return time.Duration(n).Microseconds()
-}
-
 func runStatLinePrinter(ctx context.Context, printer *Printer, addr string, intervalStats time.Duration, mergeResultsEachHost bool) {
 	go func() {
 		ticker := time.NewTicker(intervalStats)

printer.go

@@ -9,6 +9,14 @@ import (
 	"github.com/rcrowley/go-metrics"
 )
 
+func toMicroseconds(n int64) int64 {
+	return time.Duration(n).Microseconds()
+}
+
+func toMicrosecondsf(n float64) int64 {
+	return time.Duration(n).Microseconds()
+}
+
 type Printer struct {
 	writer io.Writer
 }
@@ -104,4 +112,4 @@ func (p *Printer) PrintJSONLinesReport(addrs []string, mergeResultsEachHost bool
 			fmt.Fprintf(p.writer, "Error encoding JSON result: %v\n", err)
 		}
 	}
-}
+}