Add canonical OP#6 test for anonymous instance validation (UUID id + type field)

[GeraBart]

Context

The GTS spec (section 3.7) defines anonymous instances as objects with an opaque UUID id and a separate type field carrying the GTS schema reference:

{
  "id": "7a1d2f34-5678-49ab-9012-abcdef123456",
  "type": "gts.x.core.events.type.v1~x.commerce.orders.order_placed.v1.0~",
  ...
}

The ./examples/events folder includes anonymous event instances following this pattern. Section 9.9 states: "Support UUIDs (format: uuid) for instance id fields."

However, all existing OP#6 (Schema Validation) tests use well-known chained GTS instance IDs for both registration and validation. There is no canonical test that:

1. Registers an anonymous instance with a UUID id + type field
2. Validates it via /validate-instance using the UUID as the instance identifier

Problem

Without a canonical test, implementations may not support the anonymous instance validation path described in the spec. For example, gts-ts currently rejects UUID-based instance IDs in validateInstance() because parseGtsID() requires the gts. prefix and proper segment format.

Proposed Test

Add an OP#6 test case that:

1. Registers a schema (e.g., the existing gts.x.test6.events.type.v1~)
2. Registers an anonymous instance with id: "<uuid>" and type: "<schema-id>"
3. Calls /validate-instance with the UUID as instance_id
4. Asserts validation succeeds (or defines how anonymous instances should be validated)

Related

• Section 3.7: Well-known and Anonymous Instances
• Section 9.1: Field naming recommendations (id, type)
• Section 9.9: UUID as object IDs
• Support for alternative gts.<type>.<instance_id> pattern notation #54: Alternative gts.<type>~<UUID> notation (related but different — that's about combined IDs, this is about the separate id/type pattern)