[Discover][A11y] Add underline to search result highlights

[akowalska622]

Summary

Closes #214592

This PR adds text-decoration: dotted underline to search result highlights due to accessibility reasons.

Checklist

Check the PR satisfies following conditions.

Reviewers should verify this PR satisfies this list as well.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• If a plugin configuration key changed, check if it needs to be allowlisted in the cloud and added to the docker list
• This was checked for breaking HTTP API changes, and any breaking changes have been approved by the breaking-change committee. The release_note:breaking label should be applied in these situations.
• Flaky Test Runner was used on any tests changed
• The PR description includes the appropriate Release Notes section, and the correct release_note:* label is applied per the guidelines
• Review the backport guidelines and apply applicable backport:* labels.

Identify risks

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Describe the risk, its severity, and mitigation for each identified risk. Invite stakeholders and evaluate how to proceed before merging.

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• ...

[elasticmachine]

Pinging @elastic/kibana-accessibility (Project:Accessibility)

[elasticmachine]

Pinging @elastic/kibana-data-discovery (Team:DataDiscovery)

[davismcphee]

Changes look good overall!

Unfortunately no good deed goes unpunished in Kibana, and this causes a weird issue in the summary columns for o11y profiles where the badge values disappear 🫠

highlight.mp4

Luckily I had an idea of why this was happening since I knew they were doing some fancy stuff with highlights to support those badges... Looks like we probably just need to update some regex here to account for attributes on mark tags. I'd recommend trying to make it generic, i.e. ignore any attributes, to protect against any similar changes in the future:

kibana/src/platform/packages/shared/kbn-discover-contextual-components/src/data_types/logs/components/utils/truncate_preserve_highlight_tags.ts

Lines 10 to 18 in c726ced

	function extractTextAndMarkTags(html: string) {
	const markTags: string[] = [];
	const cleanText = html.replace(/<\/?mark>/g, (match) => {
	markTags.push(match);
	return '';
	});
	return { cleanText, markTags };
	}

[akowalska622]

@davismcphee wow, thank you! This shows how important is a review from someone more experienced with the product, I wouldn't even know it can break like this

[akowalska622]

New regex matches any additional props added to mark tag, before closing >.
It fixes a bug which was introduced with a new styling class added to mark - current regex was incorrectly recognizing tags and clean text

[elasticmachine]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: f236c8a

Failed CI Steps

• FTR Configs #110

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
discover	1.1MB	1.1MB	+5.0B

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
core	475.4KB	475.4KB	+55.0B
fieldFormats	57.4KB	57.4KB	+28.0B
total			+83.0B

History

• 💛 Build #320689 was flaky ef2b84e
• 💚 Build #320360 succeeded 6e01b42
• 💔 Build #320320 failed 9e13882
• 💚 Build #319697 succeeded 1985c1d
• 💔 Build #319526 failed 6b6116d

cc @akowalska622

[davismcphee]

Thanks for the updates! Works great with the latest changes, and I confirmed the issue with the summary badges is now resolved 👍

[eokoneyo]

Shared UX LGTM