Extended 'Save all chart images' button to allow subset of charts to be generated

[WolfyUK]

Context

AB#248191 AB#245257 #1825

Change proposed in this pull request

• Renamed <ModalSaveAllImages /> component to <ModalSaveImages />, but retained original functionality via optional prop
• Refactored out ARIA progress component as well as modal/CTA components
• List as checkboxes all charts to be generated, allowing user to un/check as required (default: all checked)
• Validation error if no charts selected
• Disable initial button press on Benchmark Spending pages until data loaded

Guidance to review

Dependency on #1825.

Checklist (add/remove as appropriate)

• Work items have been linked (use AB#)
• Your code builds clean without any errors or warnings
• You have run all unit/integration tests and they pass
• Your branch has been rebased onto main
• You have tested by running locally
• You have reviewed with UX/Design