- for easier dev readability and atomic styles

+ rename generic `iconButton` name to a more accurate `arrow` and remove className modifiers (use `[aria-expanded]` instead of `-isOpen`

+ inline some very minimal styles that don't require euiTheme or modifiers (trigger wrapper & optional action - action needs a label to trigger emotion snapshot serializer logic)

- order imports by specificity

- order destrucuted props by approximate usage

- remove unnecessary newlines

- allows us to use more succinct useEffect/useRefs

+ remove extra unnecessary div wrapper (not really sure what it was even doing)

+ remove extra loading styles in favor of a quick inline one-liner

…rectly

- this feels more react-y and has the benefit of not requiring an extra useEffect on mount

…instead

- see https://developer.mozilla.org/en-US/docs/Web/HTML/Global_attributes/inert - this property completely does what we want and full browser support was added in early 2023

- also allows us to remove `visibility` CSS which we were using to hide content from screen readers

- remove CSS overrides in favor of two separate states

- add missing motion media query around height/opacity transition

- remove complete focus removal in favor of `:focus-visible` selector and existing mixin

- add `left` and `right` CSS keys

- add open/closed CSS keys while we're here

- update snapshots