Disable OpenAPIKit parameterStyleAndLocationAreCompatible validator

[simonjbeaumont]

Motivation

After updating to OpenAPIKit 6.0 (#875), the generator fails on OpenAPI documents that use style: simple on query parameters. While this is technically invalid per the OpenAPI specification, it was previously tolerated -- the generator would skip the unsupported parameter with a warning diagnostic and continue generation.

The new OpenAPIKit 6.0 brings a new default built-in validation (.parameterStyleAndLocationAreCompatible) that rejects documents with this combination at validation time. Because this fires as a validation error (not a warning), it is thrown even with strict: false, before the translator gets a chance to handle the parameter gracefully.

This is a regression for users with documents that have this common spec violation, which we do have examples of in our extended compatibility test suite).

Modifications

Replace the use of Validator() (which includes all OpenAPIKit defaults) with a custom validator built from Validator.blank. This explicitly lists all default validations from OpenAPIKit 6.0.0 except .parameterStyleAndLocationAreCompatible, restoring the previous behaviour where the generator tolerates these documents.

We might want to revisit how lenient we are for this, but this patch is the most expeditious way to getting a release out with the OpenAPIKit update.

Result

Documents with style: simple on query parameters are no longer rejected at validation time. The translator continues to emit an "unsupported" diagnostic and skip the parameter, as it did before the OpenAPIKit upgrade:

'Feature "Query params of style simple, explode: false" is not supported, skipping'