Fetch public manifest signing key metadata.

Fetch public manifest signing key metadata.

Inputs. No path or query fields are required. No request body is required.

Outputs. See each status below for its media type, schema and headers. A missing record or unavailable capability is not a successful empty result.

Errors. API JSON failures use the documented response schema. Read code, message and next; retry only when the response allows it. Auth, invalid input and missing records need a caller change.

Rate limits. Public read budgets apply by client IP and route group. This operation can have a smaller route-specific budget. Read Retry-After on 429 or retryable 503 responses.