feat: improve DataTable keyboard accessibility for issue #2320

[siarhei-epam]

Description:

This MR implements keyboard accessibility improvements for DataTable components to comply with WCAG 2.1.1 standards.

Changes Made

New Components:

• ControlIcon - New accessible icon button component with keyboard support, tabIndex management, ARIA labeling, and focus-visible styling

Enhanced Components:

• DataTableHeaderCell - Added keyboard handlers for sorting and filter dropdowns (Enter/Space keys), proper tabIndex management
• KeyboardUtils - Enhanced handleDataSourceKeyboard function with better focus management and Enter key handling for virtual lists
• DataPickerRow - Added proper focus handling
• DataRowAddons - Added isFoldingFocusable prop for better focus control

Accessibility Standards Addressed

• WCAG 2.1.1 Keyboard (Level A) - All functionality available via keyboard
• WCAG 2.4.3 Focus Order (Level A) - Logical focus sequence
• WCAG 4.1.2 Name, Role, Value (Level A) - Proper ARIA implementation

Implementation Notes

1. The focus size on the LinkButton in pickers and filters extends beyond the container.
2. When clearing a value in a single picker, the focus becomes invisible because the "Clear" button's state changes to disabled.
3. It is difficult to implement folding by keyboard in tables that contain trees. When certain parts are folded, the focus shifts to the base because the DOM tree is recreated.
4. Navigating through dates with arrow keys instead of the Tab key is difficult, time-consuming, and does not follow established patterns.
5. The focus can sometimes be hidden behind fixed columns.

Issue link:

• [Data Table]: accessibility issues related to the component #2320

QA notes:

[github-actions]

Generated by: track-bundle-size
Generated at: Mon, 27 Oct 2025 15:14:47 GMT
Bundle size diff (in kBytes). Not gzipped. Both CSS & JS included.
Baseline: v6.1.5-beta.1 (2025-07-15)
CI Status: ok

Module	Baseline Size (v6.1.5-beta.1)	Size	Diff	Within Threshold	Threshold (min - max)
templateApp	646.65	694.63	+47.98 js:+22.11 css:+25.87	🆗	581.98 - 711.31
@epam/app	5368.95	5584.05	+215.1 js:+189.12 css:+25.98	🆗	4832.06 - 5905.85
@epam/electric	5.03	5.04	+0.01 js:+0.01 css:0	🆗	4.53 - 5.54
@epam/promo	55.43	55.61	+0.18 js:+0.01 css:+0.18	🆗	49.89 - 60.97
@epam/uui-extra	0.21	0.21	0 js:0 css:0	🆗	0.19 - 0.23
@epam/loveship	92.62	92.82	+0.2 js:+0.02 css:+0.18	🆗	83.35 - 101.88
@epam/uui-components	251.75	252.23	+0.48 js:+0.13 css:+0.35	🆗	226.58 - 276.93
@epam/uui-core	325.46	324.36	-1.1 js:-1.1 css:0	🆗	292.92 - 358.01
@epam/uui-db	41.63	41.63	0 js:0 css:0	🆗	37.47 - 45.8
@epam/uui-docs	179.06	181.03	+1.97 js:+1.97 css:0	🆗	161.15 - 196.96
@epam/uui-editor	173.82	174.1	+0.28 js:+0.24 css:+0.04	🆗	156.44 - 191.2
@epam/uui-timeline	75.5	75.5	+0 js:+0 css:0	🆗	67.95 - 83.04
@epam/uui	503.4	529.24	+25.84 js:+17.61 css:+8.23	🆗	453.06 - 553.74

new sizes (raw)

To set the sizes as a new baseline, you can copy/paste next content to the uui-build/config/bundleSizeBaseLine.json and commit the file.

{
  "version": "6.3.1",
  "timestamp": "2025-10-27",
  "sizes": {
    "templateApp": {
      "css": 259422,
      "js": 451877
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    "@epam/app": {
      "css": 722404,
      "js": 4995665
    },
    "@epam/electric": {
      "css": 2275,
      "js": 2883
    },
    "@epam/promo": {
      "css": 47803,
      "js": 9145
    },
    "@epam/uui-extra": {
      "css": 0,
      "js": 213
    },
    "@epam/loveship": {
      "css": 55379,
      "js": 39666
    },
    "@epam/uui-components": {
      "css": 23582,
      "js": 234701
    },
    "@epam/uui-core": {
      "css": 0,
      "js": 332147
    },
    "@epam/uui-db": {
      "css": 0,
      "js": 42633
    },
    "@epam/uui-docs": {
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      "js": 183212
    },
    "@epam/uui-editor": {
      "css": 12953,
      "js": 165326
    },
    "@epam/uui-timeline": {
      "css": 2201,
      "js": 75109
    },
    "@epam/uui": {
      "css": 200377,
      "js": 341564
    }
  }
}

---

Generated by: generate-components-api
CI Status: ok

Total amount of exported types/props without JSDoc comments

	Amount
Types	336 (+0) 🆗
Props	221 (+0) 🆗