[Epic] Multi-Cloud Support

[thealphacubicle]

Overview

Tracks all work to extend OpenContext deployments beyond AWS to GCP and Azure.
The cloud-agnostic adapter pattern (#19) is already complete and merged, which
unblocks GCP and Azure Terraform configurations. Enhanced caching strategy
across all CSPs is the final item in this epic.

Child Issues

• [GCP] Implement complete Terraform configuration ([GCP] Implement complete Terraform configuration #5)
• [Azure] Implement complete Terraform configuration ([Azure] Implement complete Terraform configuration #6)
• [Infrastructure] Implement enhanced caching strategy across all CSPs ([Infrastructure] Implement enhanced caching strategy across all CSPs #14)

Notes

• Owner: Partner dev
• [GCP] Implement complete Terraform configuration #5 and [Azure] Implement complete Terraform configuration #6 are existing issues — add them as sub-issues directly
• [GCP] Implement complete Terraform configuration #5 and [Azure] Implement complete Terraform configuration #6 are fully independent and can be worked in parallel by
  two people
• [Infrastructure] Implement enhanced caching strategy across all CSPs #14 is the last in sequence — should only begin once [GCP] Implement complete Terraform configuration #5 and [Azure] Implement complete Terraform configuration #6
  are both complete and verified
• Coordinate health check endpoint work with Observability epic (#XX) —
  health checks must work identically across all three clouds