fix: address CodeRabbit nitpicks, consistent output formatting

error.go

@@ -265,7 +265,7 @@ func WriteErr(api API, ctx Context, status int, msg string, errs ...error) error
 	writeErr := writeResponse(api, ctx, status, "", err)
 	if writeErr != nil {
 		// If we can't write the error, log it so we know what happened.
-		fmt.Fprintf(os.Stderr, "could not write error: %s\n", writeErr)
+		fmt.Fprintf(os.Stderr, "could not write error: %v\n", writeErr)
 	}
 	return writeErr
 }

sse/sse.go

@@ -161,10 +161,10 @@ func Register[I any](api huma.API, op huma.Operation, eventTypeMap map[string]an
 				send := func(msg Message) error {
 					if deadliner != nil {
 						if err := deadliner.SetWriteDeadline(time.Now().Add(WriteTimeout)); err != nil {
-							fmt.Fprintln(os.Stderr, "warning: unable to set write deadline: "+err.Error())
+							fmt.Fprintf(os.Stderr, "warning: unable to set write deadline: %v\n", err)
 						}
 					} else {
-						fmt.Fprintln(os.Stderr, "warning: unable to set write deadline")
+						fmt.Fprintln(os.Stderr, "write deadline not supported by underlying writer")
 					}
 
 					// Write optional fields
@@ -177,7 +177,7 @@ func Register[I any](api huma.API, op huma.Operation, eventTypeMap map[string]an
 
 					event, ok := typeToEvent[deref(reflect.TypeOf(msg.Data))]
 					if !ok {
-						fmt.Fprintln(os.Stderr, "error: unknown event type", reflect.TypeOf(msg.Data))
+						fmt.Fprintf(os.Stderr, "error: unknown event type %v\n", reflect.TypeOf(msg.Data))
 						debug.PrintStack()
 					}
 					if event != "" && event != "message" {