Stop using the 'backend' parameter and rely only on cluster name

[adameat]

Currently, the system relies on the 'backend' parameter, which both exposes it and requires it for operation. To improve security and usability, the application should stop displaying or accepting the 'backend' parameter entirely. Instead, all logic should be based solely on the cluster name. This will ensure that sensitive or unnecessary parameters are not handled, reducing potential attack vectors and simplifying the workflow.

Acceptance criteria:

• Remove any UI and API references to the 'backend' parameter.
• Ensure that the system does not accept, display, or require the 'backend' parameter in any workflow.
• Refactor logic to use only the cluster name for all relevant operations.
• Update documentation and tests as needed to reflect this change.

Benefits:

• Improved security by not exposing the 'backend' parameter.
• Simplified configuration and user experience.
• Reduced risk of misconfiguration or parameter leakage.