[8.18] fix: [Analytics:Graph page]Dialog modal missing title from announcement (elastic#217827) (elastic#218423)

# Backport

This will backport the following commits from `main` to `8.18`:
- [fix: [Analytics:Graph page]Dialog modal missing title from
announcement (elastic#217827)](elastic#217827)

<!--- Backport version: 9.6.6 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

<!--BACKPORT [{"author":{"name":"Alexey
Antonov","email":"[email protected]"},"sourceCommit":{"committedDate":"2025-04-16T12:03:38Z","message":"fix:
[Analytics:Graph page]Dialog modal missing title from announcement
(elastic#217827)\n\nCloses: elastic#214760\n\n**Description**\nDialog modal, flyout,
field visible title should be announced for the\nusers, especially using
assistive technology to know what dialog modal,\nflyout opened, what
field is active and what is needed to enter in it.\n\n**Changes
made:**\n\n1. Set correct value for` aria-labelledby`
attr.","sha":"b91da375a3c965181e2b2ee6f899d42ee6dcc0f0","branchLabelMapping":{"^v9.1.0$":"main","^v8.19.0$":"8.x","^v(\\d+).(\\d+).\\d+$":"$1.$2"}},"sourcePullRequest":{"labels":["Project:Accessibility","release_note:skip","backport:prev-major","v9.1.0"],"title":"fix:
[Analytics:Graph page]Dialog modal missing title from
announcement","number":217827,"url":"https://github.com/elastic/kibana/pull/217827","mergeCommit":{"message":"fix:
[Analytics:Graph page]Dialog modal missing title from announcement
(elastic#217827)\n\nCloses: elastic#214760\n\n**Description**\nDialog modal, flyout,
field visible title should be announced for the\nusers, especially using
assistive technology to know what dialog modal,\nflyout opened, what
field is active and what is needed to enter in it.\n\n**Changes
made:**\n\n1. Set correct value for` aria-labelledby`
attr.","sha":"b91da375a3c965181e2b2ee6f899d42ee6dcc0f0"}},"sourceBranch":"main","suggestedTargetBranches":[],"targetPullRequestStates":[{"branch":"main","label":"v9.1.0","branchLabelMappingKey":"^v9.1.0$","isSourceBranch":true,"state":"MERGED","url":"https://github.com/elastic/kibana/pull/217827","number":217827,"mergeCommit":{"message":"fix:
[Analytics:Graph page]Dialog modal missing title from announcement
(elastic#217827)\n\nCloses: elastic#214760\n\n**Description**\nDialog modal, flyout,
field visible title should be announced for the\nusers, especially using
assistive technology to know what dialog modal,\nflyout opened, what
field is active and what is needed to enter in it.\n\n**Changes
made:**\n\n1. Set correct value for` aria-labelledby`
attr.","sha":"b91da375a3c965181e2b2ee6f899d42ee6dcc0f0"}}]}] BACKPORT-->

Co-authored-by: Alexey Antonov <[email protected]>

Author: kibanamachine

src/core/packages/overlays/browser/src/modal.ts

@@ -7,7 +7,7 @@
  * License v3.0 only", or the "Server Side Public License, v 1".
  */
 
-import type { EuiConfirmModalProps } from '@elastic/eui';
+import type { EuiConfirmModalProps, EuiModalProps } from '@elastic/eui';
 import type { MountPoint, OverlayRef } from '@kbn/core-mount-utils-browser';
 
 /**
@@ -22,6 +22,7 @@ export interface OverlayModalConfirmOptions {
   'data-test-subj'?: string;
   defaultFocusedButton?: EuiConfirmModalProps['defaultFocusedButton'];
   buttonColor?: EuiConfirmModalProps['buttonColor'];
+  'aria-labelledby'?: EuiConfirmModalProps['aria-labelledby'];
   /**
    * Sets the max-width of the modal.
    * Set to `true` to use the default (`euiBreakpoints 'm'`),
@@ -66,4 +67,5 @@ export interface OverlayModalOpenOptions {
   closeButtonAriaLabel?: string;
   'data-test-subj'?: string;
   maxWidth?: boolean | number | string;
+  'aria-labelledby'?: EuiModalProps['aria-labelledby'];
 }

x-pack/platform/plugins/private/graph/public/components/source_modal.tsx

@@ -15,7 +15,7 @@ export function SourceModal(props: SourcePickerProps) {
   return (
     <div className="gphSourceModal">
       <EuiModalHeader>
-        <EuiModalHeaderTitle>
+        <EuiModalHeaderTitle id="source-modal-title">
           <FormattedMessage
             id="xpack.graph.sourceModal.title"
             defaultMessage="Select a data source"

x-pack/platform/plugins/private/graph/public/services/source_modal.tsx

@@ -32,6 +32,9 @@ export function openSourceModal(
         onSelected(indexPattern);
         modalRef.close();
       }}
-    />
+    />,
+    {
+      'aria-labelledby': 'source-modal-title',
+    }
   );
 }