- Assert DeviceType defaults to "routeros" via COALESCE
- Assert SNMPPort defaults to 161 via COALESCE
- Assert SNMPVersion, SNMPProfileID, CredentialProfileID are nil for
existing RouterOS devices without profile links
- Assert ProfileEncryptedCredentials and ProfileEncryptedCredentialsTransit
are nil when no credential profile is linked
- Update test schema with device_type, snmp_port, snmp_version,
snmp_profile_id, credential_profile_id columns
- Add credential_profiles table to test schema for LEFT JOIN
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>