add initial stuff

internal/tui/util/util.go

@@ -16,3 +16,10 @@ type (
 	InfoMsg  string
 	ErrorMsg error
 )
+
+func Clamp(v, low, high int) int {
+	if high < low {
+		low, high = high, low
+	}
+	return min(high, max(low, v))
+}