Add provider-driven sync for shared RERUM OpenAPI artifacts

[Copilot]

This adds the provider-side wiring for a shared RERUM OpenAPI artifact so changes in this repo can trigger sync PRs in cubap/rerum_openapi. It also establishes the canonical provider path and keeps the in-repo target artifact present for update-based sync workflows.

• Provider-driven sync workflow

  • Adds a GitHub Actions workflow that watches:
    • openapi/components/rerum-shared-components.openapi.yaml
  • Dispatches sync-provider-artifact.yml in cubap/rerum_openapi
  • Passes the provider repo/ref and the source/target artifact paths expected by the receiver workflow

• Canonical shared artifact layout

  • Adds the provider-owned shared component artifact at:
    • openapi/components/rerum-shared-components.openapi.yaml
  • Uses a standard OpenAPI directory layout so the source artifact is easy to find and update

• Pre-created sync target

  • Adds:
    • schemas/openapi/rerum-shared-components.openapi.yaml
  • Keeps the target file stubbed in-repo so downstream sync updates modify an existing artifact instead of creating a new one
  • Marks the target as an auto-synced copy to reduce ambiguity about ownership

• Focused guardrails

  • Adds a narrow test that verifies:
    • both shared artifact files exist with the expected OpenAPI scaffold
    • the workflow is wired to the correct source file, receiver workflow, and target path

inputs:
  provider_repository: ${{ github.repository }}
  provider_ref: ${{ github.sha }}
  provider_artifact_path: openapi/components/rerum-shared-components.openapi.yaml
  target_artifact_path: schemas/openapi/rerum-shared-components.openapi.yaml

Warning

Firewall rules blocked me from connecting to one or more addresses (expand for details)

I tried to connect to the following addresses, but was blocked by firewall rules:

• test.auth0.com
  • Triggering command: /home/REDACTED/work/_temp/ghcca-node/node/bin/node node ./bin/rerum_v1.js (dns block)

If you need me to access, download, or install something from one of these locations, you can either:

• Configure Actions setup steps to set up my environment, which run before the firewall is enabled
• Add the appropriate URLs or hosts to the custom allowlist in this repository's Copilot coding agent settings (admins only)