Accept transparent proxy config from Dataplane Metadata

[bartsmykla]

Summary

Update the control plane to support receiving transparent proxy configuration via Dataplane Metadata instead of the Dataplane resource definition.

Background

As part of the work described in the MADR Transparent Proxy ConfigMap Handling Outside the Control Plane, we are moving toward configuring transparent proxy settings via CLI and passing them through Dataplane Metadata. This change is necessary to remove the requirement for the control plane to access ConfigMaps in all namespaces.

Tasks

• Update the control plane to read transparent proxy settings from Dataplane Metadata
• Ensure the metadata-based config takes precedence over values defined directly in the Dataplane resource

Acceptance Criteria

• Metadata-based config is preferred when present
• Old config path remains supported for compatibility
• Functionality is verified through tests and documentation is updated accordingly