fix(Wait Node): Add validation for wait amount and unit (#18239)

packages/nodes-base/nodes/Wait/validation.ts

@@ -0,0 +1,8 @@
+export function validateWaitAmount(amount: unknown): amount is number {
+	return typeof amount === 'number' && amount > 0;
+}
+
+export type WaitUnit = 'seconds' | 'minutes' | 'hours' | 'days';
+export function validateWaitUnit(unit: unknown): unit is WaitUnit {
+	return typeof unit === 'string' && ['seconds', 'minutes', 'hours', 'days'].includes(unit);
+}