LG-4622: Adds a loading state to the Chart component

[tsck]

✍️ Proposed changes

• Adds a loading state to the Chart component
• Designs

🎟 Jira ticket: LG-4622

✅ Checklist

For bug fixes, new features & breaking changes

• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)
• I have run pnpm changeset and documented my changes

For new components

• I have added my new package to the global tsconfig
• I have added my new package to the Table of Contents on the global README
• I have verified the Live Example looks as intended on the design website.

🧪 How to test changes

Test via isLoading prop in storybook

Screenshot

[changeset-bot]

🦋 Changeset detected

Latest commit: fc8e9e0

The changes in this PR will be included in the next version bump.

This PR includes changesets to release 1 package

Name	Type
@lg-charts/core	Minor

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[stephl3]

is there any possibility we might want to render an error if chart data doesn't load or encounters some other issue? if so, I'm curious what you think about using a more extensible enum rather than a boolean for state

[tsck]

This is a very good callout. Internal Tools had mentioned an error state as well and I meant to talk to Sooa about this. There's nothing in the designs for this but there probably should be. I will definitely update it so that there's an enum rather than a boolean for this case, and I'll ping design about the error state (though will probably add that separately, assuming design wants it)

[stephl3]

We also have loading/error states in Combobox and SearchInput and those use Unset: 'unset' instead of Default: 'default'. Can we use the same for consistency?

leafygreen-ui/packages/combobox/src/types/Combobox.types.ts

Lines 53 to 58 in c406ab8

	export const SearchState = {
	Unset: 'unset',
	Error: 'error',
	Loading: 'loading',
	} as const;
	export type SearchState = (typeof SearchState)[keyof typeof SearchState];