Add persistent storage for Keycloak data

[Serumola]

Goal

• Make sure Keycloak keeps its data after EC2 restarts.

Description

• Right now, if the container or machine restarts, Keycloak may lose important state unless persistence is configured correctly. We need to make sure realms, users, clients, and settings survive restarts.

Why this matters

• Users should not lose their accounts or configuration just because the server rebooted or the container restarted.

Tasks

• Choose a persistence strategy for Keycloak
• Decide whether to use a database or mounted volume
• Ensure realm and user data survive restarts
• Confirm the setup recovers correctly after reboot or update
• Acceptance criteria
• Keycloak data survives container restarts
• Realms and clients remain available after reboot
• The deployment is durable enough for AWS use