chore(design-system): add system time mock to date tests [AR-46279]

packages/design-system/src/components/ds-date-input/ds-date-input.stories.tsx

@@ -1,17 +1,29 @@
 import type { Meta, StoryObj } from '@storybook/react-vite';
 import { useState } from 'react';
 import { expect, screen, userEvent, waitFor, within } from 'storybook/test';
+import { vi } from 'vitest';
 import DsDateInput from './ds-date-input';
 import type { DsDateInputProps } from './ds-date-input.types';
 import styles from './ds-date-input.stories.module.scss';
 
+// Mock system time to January 15, 2026 for consistent test dates
+const MOCK_DATE = new Date('2026-01-15T12:00:00');
+
 const meta: Meta<typeof DsDateInput> = {
 	title: 'Design System/DateInput',
 	component: DsDateInput,
 	tags: ['autodocs'],
 	parameters: {
 		layout: 'centered',
 	},
+	beforeEach: () => {
+		vi.useFakeTimers();
+		vi.setSystemTime(MOCK_DATE);
+
+		return () => {
+			vi.useRealTimers();
+		};
+	},
 };
 
 export default meta;
@@ -20,7 +32,7 @@
 /**
  * Basic single date input with default configuration
  */
 export const Default: Story = {
 	render: function Render() {
 		const [value, setValue] = useState<string>();
 
@@ -82,7 +94,7 @@
 /**
  * Date range input - unified input field for start and end dates
  */
 export const RangeMode: Story = {
 	render: function Render() {
 		const [value, setValue] = useState<[string, string]>();
 
@@ -160,7 +172,7 @@
 /**
  * Single date input with pre-filled value
  */
 export const WithDefaultValue: Story = {
 	args: {
 		className: styles.containerSingle,
 		defaultValue: '2024-12-25',
@@ -170,7 +182,7 @@
 /**
  * Range input with pre-filled values
  */
 export const RangeWithDefaultValue: Story = {
 	args: {
 		className: styles.containerRange,
 		defaultValue: ['2024-12-01', '2024-12-31'],
@@ -181,7 +193,7 @@
 /**
  * Date input with min and max constraints
  */
 export const WithMinMax: Story = {
 	render: function Render() {
 		const [value, setValue] = useState<string>();
 		const today = new Date();
@@ -206,7 +218,7 @@
 /**
  * Disabled date input
  */
 export const Disabled: Story = {
 	args: {
 		className: styles.containerSingle,
 		value: '2024-12-25',
@@ -217,7 +229,7 @@
 /**
  * Read-only date input
  */
 export const ReadOnly: Story = {
 	args: {
 		className: styles.containerSingle,
 		value: '2024-12-25',
@@ -228,7 +240,7 @@
 /**
  * Controlled open state
  */
 export const ControlledOpen: Story = {
 	render: function Render() {
 		const [value, setValue] = useState<string>();
 		const [open, setOpen] = useState(false);
@@ -247,7 +259,7 @@
 /**
  * Uncontrolled with defaultValue
  */
 export const Uncontrolled: Story = {
 	render: function Render() {
 		return (
 			<div className={styles.containerSingle}>