Test: Add test cases for space key behavior with showSearch

Added test coverage to verify space key behavior in different Select modes:

1. showSearch enabled: Space should NOT call preventDefault, allowing space to be typed
2. showSearch disabled: Space SHOULD call preventDefault, preventing page scroll
3. combobox mode: Space should NOT call preventDefault, allowing space to be typed

These tests ensure the fix correctly handles space key input based on whether the input is editable.

Author: zombieJ

tests/spaceInput.test.tsx

@@ -0,0 +1,63 @@
+import * as React from 'react';
+import { render } from '@testing-library/react';
+import Select from '../src/Select';
+
+describe('Space key behavior with showSearch', () => {
+  it('should not call preventDefault on space when showSearch is enabled', () => {
+    const { container } = render(
+      <Select showSearch options={[{ value: 'test', label: 'test' }]} />,
+    );
+
+    const input = container.querySelector('input');
+    input.focus();
+
+    const keyDownEvent = new KeyboardEvent('keydown', {
+      key: ' ',
+      code: 'Space',
+      bubbles: true,
+    });
+    const preventDefaultSpy = jest.spyOn(keyDownEvent, 'preventDefault');
+
+    input.dispatchEvent(keyDownEvent);
+
+    expect(preventDefaultSpy).not.toHaveBeenCalled();
+  });
+
+  it('should call preventDefault on space when showSearch is disabled', () => {
+    const { container } = render(<Select options={[{ value: 'test', label: 'test' }]} />);
+
+    const input = container.querySelector('input');
+    input.focus();
+
+    const keyDownEvent = new KeyboardEvent('keydown', {
+      key: ' ',
+      code: 'Space',
+      bubbles: true,
+    });
+    const preventDefaultSpy = jest.spyOn(keyDownEvent, 'preventDefault');
+
+    input.dispatchEvent(keyDownEvent);
+
+    expect(preventDefaultSpy).toHaveBeenCalled();
+  });
+
+  it('should not call preventDefault on space in combobox mode', () => {
+    const { container } = render(
+      <Select mode="combobox" options={[{ value: 'test', label: 'test' }]} />,
+    );
+
+    const input = container.querySelector('input');
+    input.focus();
+
+    const keyDownEvent = new KeyboardEvent('keydown', {
+      key: ' ',
+      code: 'Space',
+      bubbles: true,
+    });
+    const preventDefaultSpy = jest.spyOn(keyDownEvent, 'preventDefault');
+
+    input.dispatchEvent(keyDownEvent);
+
+    expect(preventDefaultSpy).not.toHaveBeenCalled();
+  });
+});