Refactor Form and Billboard with Proposed Component Standards

[HarveyPeachey]

Resolves JIRA:

Summary

Moves Billboard component, to be colocated with the Curation component, as that's the only component using it. Refactors form to fit the component standards methods of using context and exporting components.

Code changes

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Developer Checklist

• UX
  • UX Criteria met (visual UX & screenreader UX)
• Accessibility
  • Accessibility Acceptance Criteria met
  • Accessibility swarm completed
  • Component Health updated
  • P1 accessibility bugs resolved
  • P2/P3 accessibility bugs planned (if not resolved)
• Security
  • Security issues addressed
  • Threat Model updated
• Documentation
  • Docs updated (runbook, READMEs)
• Testing
  • Feature tested on relevant environments
• Comms
  • Relevant parties notified of changes

Testing

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  • Live (Ready-For-Test, Live)
• Manual Testing complete?
  • Local
  • Test
  • Preview
  • Live

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