Goal: 

Create documentation for Barbican adoption from RHOSP 17.1 to RHOSO 18 with Proteccio HSM, extending the existing simple_crypto documentation to include PKCS11/HSM backend procedures.

Acceptance Criteria:

• Create new AsciiDoc module with complete 5-phase adoption process.
• Document OpenStackControlPlane CR configuration for HSM backend.
• Include prerequisites (HSM certificates, custom containers, ansible-role-rhoso-proteccio-hsm).
• Add environment detection guide to choose between simple_crypto vs HSM approaches.
• Create troubleshooting reference for HSM-specific issues.
• Update main assembly to include conditional HSM documentation references.
• Provide end-to-end verification steps for HSM secret storage/retrieval.
• Validate all procedures against existing barbican_proteccio_adoption role.