Args:
    readiness_content: A readiness result, as JSON text.
    remediation_content: An optional remediation result, as JSON text.
    simulation_content: An optional JSON array of simulated responses.
    metadata: Free-form audit metadata (institution, reference, ...).

Args:
    pack_content: The evidence pack to seal, as JSON text.

Args:
    pack_content: The evidence pack to check, as JSON text.
    expected_digest: The seal the pack is expected to carry.

Args:
    pack_content: The evidence pack to render, as JSON text.

The private key is configured by the operator via the environment (see
:mod:`iso20022_evidence_pack_mcp.signing`); it never crosses the tool
boundary. Returns the detached signature, the public key, and a key id;
fails with ``EP_NO_SIGNING_KEY`` when no key is configured.

Args:
    pack_content: The evidence pack to sign, as JSON text.

Args:
    pack_content: The evidence pack to check, as JSON text.
    signature: The base64-encoded detached signature.
    public_key: The signer's PEM public key.