chat customizations: fix clipping

[joshspicer]

fix #304139

Also add more examples to fixtures

[Copilot]

Pull request overview

Fixes a layout issue in the AI Customizations UI where, after switching to “Browse Marketplace” in the MCP Servers tab, the last marketplace entry could be partially clipped (missing a re-layout when the back-link appears). Also expands component-explorer fixtures to provide more realistic, scrollable datasets and adds guidance for screenshot fixtures.

Changes:

• Trigger a widget re-layout when entering/exiting browse mode in McpListWidget and PluginListWidget.
• Expand AI Customizations management editor fixtures with richer data, new per-tab screenshot fixtures, and standalone browse-mode fixtures.
• Update the chat-customizations-editor skill doc with instructions for targeting specific tab fixtures.

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
src/vs/workbench/contrib/chat/browser/aiCustomization/mcpListWidget.ts	Store last layout size and re-layout on browse-mode toggle so the list height accounts for the back-link.
src/vs/workbench/contrib/chat/browser/aiCustomization/pluginListWidget.ts	Same browse-mode re-layout behavior as MCP widget to avoid clipped content.
src/vs/workbench/test/browser/componentFixtures/aiCustomizationManagementEditor.fixture.ts	Adds richer fixture data, per-tab fixtures, and standalone browse-mode fixtures for MCP/plugins.
src/vs/workbench/test/browser/componentFixtures/aiCustomizationListWidget.fixture.ts	Adds IProductService mock to satisfy dependencies for list widget fixture rendering.
.github/skills/chat-customizations-editor/SKILL.md	Documents new tab-specific screenshot fixtures and how to add new ones.

Comments suppressed due to low confidence (1)

src/vs/workbench/test/browser/componentFixtures/aiCustomizationManagementEditor.fixture.ts:597

• This uses a fixed setTimeout(..., 50) and then manually calls widget.layout(height, width) to stabilize the screenshot. The fixed delay is prone to flakiness across CI/machines, and the explicit layout call can hide regressions in the widget’s internal browse-mode reflow. Prefer waiting for a deterministic condition (e.g., list has N items, or the loading empty state text changes) and rely on the widget’s own layout behavior.

	// Wait for the marketplace query to resolve
	await new Promise(resolve => setTimeout(resolve, 50));

	// Re-layout after browse mode
	widget.layout(height, width);