Acceptance criteria:

• Current errors it will replace:
  • sitelink-data-missing-title
  • statement-data-missing-field
  • missing-json-patch-field
  • top level fields that currently throw a mw framework exception
• HTTP status code: 400
• Error code: missing-field
• Error message: Required field missing
• Context: { "path": "{json_pointer_to_parent}", "field": "{missing_field}" }