feat: add canvas paintaings to media dialog

[charlesLoder]

The PR:

• adds the representative Canvas images to the MediaDialog component
• makes use of the Traverse class to find items more succinctly

[Copilot]

Pull Request Overview

This PR adds canvas painting images to the MediaDialog component and refactors the codebase to use the Traverse class for more efficient IIIF resource navigation.

• Implements IIIF Image Request URI utilities for dynamic image sizing
• Refactors MediaDialog to use Traverse class for finding canvas items
• Adds canvas paintings as selectable media alongside existing thumbnails and placeholders

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/plugin/utils/index.ts	Adds IIIF Image Request URI types and utility functions, updates getLabelByUserLanguage signature
src/plugin/Panel/index.tsx	Updates manifest label handling to be more defensive
src/plugin/Panel/index.test.tsx	Adds serialize mock for Canvas type in test setup
src/plugin/Panel/MediaDialog/style.module.css	Adds flex-wrap to content layout and removes commented code
src/plugin/Panel/MediaDialog/index.tsx	Major refactor to use Traverse class and add canvas paintings support

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[Copilot]

The JSDoc example has a malformed code block - it should end with three backticks instead of two.

[Copilot]

Using @ts-expect-error to bypass type checking makes the code fragile. Consider casting to the correct type or handling the type mismatch properly to maintain type safety.

Suggested change

	// @ts-expect-error - I don't want to go down the rabbit hole of type checking here
	const label = getLabelByUserLanguage(painting?.label);
	// Ensure painting.label is of the expected type for getLabelByUserLanguage
	const label = getLabelByUserLanguage(
	painting && painting.label
	? (painting.label as Parameters<typeof getLabelByUserLanguage>[0])
	: []
	);

[Copilot]

Using array index as React key is an anti-pattern that can cause rendering issues. Use a unique, stable identifier like thumbnail-${thumbnail.id} instead.