Document all data quality constraints

[siuc-nate]

For each field, we need to document:

• Whether the field is required
• Minimum character lengths
• Disallowed inputs (e.g. not allowing "N/A" for a description)
• Any other requirements

These are currently scattered across our policy page, bulk upload page, handbook(s), and API error messages. It should be possible to find all of this information in one spot. Perhaps this is something that could be programmatically controlled/generated, so it's always up to date?

[siuc-nate]

This would also play into our (eventual) shex/shacl implementation, and likely also be used on our policy page. So if it can be done programmatically, that would be good.

[mparsons-ce]

The minimum data policy should handle the documentation of required properties. Each section includes a link to the related section under under minimum data. We don't want to start duplicating sections.
In the API input classes, a region is used to group required properties.

I will add a section to the API handbook regarding data quality/reasonability checks, including

• minimum lengths for descriptions
• URL checking
• Organization URLs must exist in the registry
• Situations like where a credential can refer to a lopp and the lopp doesn't have to already exist in the registry
• Other TBD