Tests run against a real Metacrypt instance, guarded by
//go:build integration tag and METACRYPT_LIVE_TEST=1 env var.
Covers: directory discovery, nonce issuance, full account creation
with EAB (including reuse rejection), order creation with DNS
identifiers, and authorization retrieval with HTTP-01/DNS-01
challenges.
Handles server/client URL mismatch when ExternalURL is not
configured (JWS URL fields use server's base URL, HTTP requests
use the configured address).
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>