Loading state/error state for conversation history

[rebeccaalpert]

RHDH is looking for a loading state, empty state, and error state for conversation history.

Waiting on patternfly/patternfly-design-kit#774 and patternfly/patternfly-design-kit#775.

[kaylachumley]

This is ready to go! I updated the figma kit to reflect the design changes.

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Error state is using a empty state with status component to represent failed content. The icon status color is using pf-t--global--icon--color--status--danger--default

Error State Dark Mode:

Error State Light Mode:

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The loading state, per Andrews recommendation, should use a skeleton loader since we are exposing content incrementally and we know what the expected content layout will be every time. Since figma has some limitations with animations and we do not yet support gradient tokens, the figma designs use a flat fill for the skeleton. The actual skeleton loader should adopt the animated gradient that's on org.

Loading State Light Mode:

Loading State Dark Mode:

[rebeccaalpert]

See #442 for empty state; breaking out separately.

[kaylachumley]

Hey! @rebeccaalpert I received some content feedback from Erin

Here is the updated copy for the error state: