fix(playback): Correct Printf formatting for right-alignment

- Fix a bug where the format string for the right-aligned prefix
  was being printed literally instead of being evaluated.
- The user message prefix now displays the timestamp and author
  correctly.

prettyFormat.go

@@ -94,7 +94,7 @@ func printLeftAligned(author, timestamp, content string) {
 }
 
 func printRightAligned(author, timestamp, content string) {
-	prefix := fmt.Sprintf(":(%%s) %%s ✦", timestamp, author)
+	prefix := fmt.Sprintf("(%s) %s ✦", timestamp, author)
 	
 	// Print the prefix first, right-aligned.
 	fmt.Printf("%*s\n", termWidth, prefix)