[Content List] Column layout props, sticky actions, and title click handlers

[clintandrewhall]

Summary

Standardizes column sizing across all Content List table presets and adds click handling to Column.Name.

• Introduces ColumnLayoutProps (width, minWidth, maxWidth, truncateText) shared by all column presets and the generic Column component, replacing the per-preset width?: string prop.
• Actions column auto-computes a default width from action count and is sticky by default for horizontal-scrolling tables.
• Adds scrollableInline and responsiveBreakpoint as props on ContentListTable with opinionated defaults (true and false respectively) to support sticky columns. Consumers can override if needed.
• Adds onClick and useHref props to Column.Name, threaded through NameCell → NameCellTitle. When both href and onClick are present, modifier clicks follow the href while plain clicks call onClick.
• Deduplicates NameCellTitle render branches from four to two.
• Adds Storybook controls for scrollableInline and responsiveBreakpoint to the Core Features story.

Changes

All changes are scoped to @kbn/content-list-table and @kbn/content-list-docs.

Area	What changed
layout.ts (new)	ColumnLayoutProps type and getColumnLayoutProps helper — standardizes width/minWidth/maxWidth/truncateText across columns.
part.ts	Generic Column component extends ColumnLayoutProps.
Name	NameColumnProps extends ColumnLayoutProps, adds onClick/useHref. NameCell and NameCellTitle thread these through. NameCellTitle collapsed from 4 render branches to 2.
Actions	Extends layout props, auto-computes default width from action count, sticky by default.
UpdatedAt, Starred, CreatedBy	Extend ColumnLayoutProps (or the relevant subset for non-text columns).
Table	New scrollableInline (default true) and responsiveBreakpoint (default false) props on ContentListTable, passed through to EuiBasicTable. Defaults enable horizontal scrolling and disable mobile card layout, which is required for sticky columns and does not support Content List features like selection, tags, and stars.
Storybook	Core Features story adds scrollableInline and responsiveBreakpoint as Storybook controls.
Tests	All builders, cell_title, and use_columns tests updated.
README	Updated code examples and documentation for layout props and onClick/useHref.

Test plan

• @kbn/content-list-table unit tests pass (155/155).
• Verify sticky actions column with horizontal overflow in Storybook.
• Verify Column.Name onClick fires on plain click, modifier clicks follow href.
• Toggle scrollableInline off in Storybook controls — table should no longer scroll horizontally.
• Toggle responsiveBreakpoint on in Storybook controls — table should collapse to cards on narrow viewports.

[elasticmachine]

Pinging @elastic/appex-sharedux (Team:SharedUX)

[kowalczyk-krzysztof]

Left some nitpick comments, otherwise LGTM

[elasticmachine]

💛 Build succeeded, but was flaky

• Buildkite Build
• Commit: 3ce035c
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Failed CI Steps

• Jest Tests #5

Test Failures

• [job] [logs] Jest Tests #5 / SelectedFilters should render properly

Metrics [docs]

Public APIs missing comments

Total count of every public API that lacks a comment. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats comments for more detailed information.

id	before	after	diff
@kbn/content-list-table	37	39	+2

Public APIs missing exports

Total count of every type that is part of your API that should be exported but is not. This will cause broken links in the API documentation system. Target amount is 0. Run node scripts/build_api_docs --plugin [yourplugin] --stats exports for more detailed information.

id	before	after	diff
@kbn/content-list-table	0	1	+1

Unknown metric groups

API count

id	before	after	diff
@kbn/content-list-table	144	148	+4

ESLint disabled line counts

id	before	after	diff
@kbn/content-list-table	1	2	+1

Total ESLint disabled count

id	before	after	diff
@kbn/content-list-table	1	2	+1