Providers catalog (read-only)

[fbarrento]

What to build

Read-only catalog endpoints. Needed before CreateServerData in the Servers slice can be properly typed (regions, sizes per provider).

Endpoints (from docs/forge.openapi.json):

• GET /providers
• GET /providers/{provider}
• GET /providers/{provider}/regions
• GET /providers/{provider}/regions/{region}
• GET /providers/{provider}/regions/{region}/sizes
• GET /providers/{provider}/regions/{region}/sizes/{size}
• GET /providers/{provider}/sizes
• GET /providers/{provider}/sizes/{size}

Source design: see project_sdk_design.md in the project's memory.

Acceptance criteria

• Provider, ProviderRegion, ProviderSize DTOs (readonly, JsonSerializable, ::from(array))
• Request classes for all 8 endpoints listed above
• ProvidersResource accessed via $forge->providers() (this is not org-scoped)
• API shape:
  • $forge->providers()->all() → list<Provider> (or Page<Provider> if the endpoint paginates — confirm from spec)
  • $forge->provider($name)->get() → Provider
  • $forge->provider($name)->regions()->all() → list of ProviderRegion
  • $forge->provider($name)->region($id)->sizes()->all() → list of ProviderSize
  • $forge->provider($name)->sizes()->all() → list of ProviderSize (region-independent)
• Tests against mocked responses for every endpoint
• composer test green

Blocked by

• Blocked by Organizations resource + Page<T> + list-options pattern #3