Resolve and improve schema references in generated OpenAPI endpoint and API JSON responses

[fmigneault]

Describe the bug

Multiple schema references are inconsistent or broken due to OGC API repository restructures.

Original references should be used for corresponding schemas.
Specific references for OGC API - Processes should be resolved.

All responses from Weaver should include a $schema reference to help machine-readable parsing and validation.

Optionally, nested objects could also offer some $schema references when those are useful for understanding the definitions.
For example, a schema field under a Process Description I/O uses JSON-schema specification to describe it.
Adding $schema: http://json-schema.org/draft-07/schema# scoped under that I/O would greatly facilitate parsing that nested object by itself without having to resolve the full parent schema that contains it.

References

• Refer to Multiple unnecessary schema redefinition opengeospatial/ogcapi-processes#320 for broken schemas or future updates about references that could be moved around.