docs: add route policies to OpenAPI spec

[rkoster]

Summary

• Document the five /v3/route_policies operations in the latest modular OpenAPI specification.
• Add route-policy schemas, request bodies, filters, relationships, includes, and standard responses.
• Keep the contract aligned with the current CAPI runtime, including comma-delimited query encoding and lifecycle error responses.

Closes #5427

Test Plan

• corepack yarn lint in docs/openapi
• corepack yarn build in docs/openapi
• Verified the bundled specification contains all route-policy paths, operations, filters, schemas, request bodies, and response statuses.

The existing lint warnings are unrelated to route policies.

[sethboyles]

Thanks @rkoster . Coincidentally, I have been working on a larger effort to get the OpenAPI docs up to date with the current v3 docs: #5432

I pulled out my two commits that added these properties, and then added some of the properties it lacked but your PR included. (also, I don't think we want the superpowers directory)

#5444
#5443