[Controls] Design pass for range slider control

[andreadelrio]

Summary

• Added a custom implementation of the read-only portion of the control (anchor) using EUI components (namely EuiFieldNumber). This replaces the previous EuiDualRange which is a bit overkill for this use case.

@cqliu1 Note: Selecting values in the popover is not changing the values in the anchor, we probably need to hook something up.

Checklist

Delete any items that are not applicable to this PR.

• Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• Any UI touched in this PR is usable by keyboard only (learn more about keyboard accessibility)
• Any UI touched in this PR does not create any new axe failures (run axe in browser: FF, Chrome)
• If a plugin configuration key changed, check if it needs to be allowlisted in the cloud and added to the docker list
• This renders correctly on smaller devices using a responsive layout. (You can test this in your browser)
• This was checked for cross-browser compatibility

For maintainers

• This was checked for breaking API changes and was labeled appropriately