feat(stand): add FullPipe DEV stand for vc_vdc and document 500 error fallback plan

- Added DEV_STAND/FullPipe with modular configuration for vc_vdc resource creation:
  - versions.tf: Terraform >= 1.5.0, provider nubes 2.0.1
  - provider.tf: nubes provider config with DEV gateway endpoint
  - variables.tf: variables for vdc (cpu=8, mem=32, guaranteed=0, fast storage=200GB)
  - vdc.tf: nubes_vc_vdc resource definition supporting org name or UUID
  - outputs.tf: vdc_id, vdc_name, vdc_state_params
  - terraform.tfvars.example: example values without secrets
- Added docs/DEBUG_REPORT_VC_VDC_500.md documenting API 500 issue in Lucee backend:
  - Error: getResourceRealmConfig fails casting Struct to string on GET /instanceOperations/{opUid}?fields=cfsParams
  - Planned changes in provider/internal/core/client.go:
    Implement graceful fallback in createInstanceWithContext to skip hard-failing
    when GET ?fields=cfsParams returns 500, since vc_vdc ref parameters (organization_uid)
    are already resolved to UUID and remaining parameters are literals/numbers.

DEV_STAND/FullPipe/vdc.tf

@@ -0,0 +1,18 @@
+resource "nubes_vc_vdc" "vdc" {
+  resource_name = var.vdc_resource_name
+
+  # Организация: имя из ЛК ("kontora") или точный UUID
+  organization_uid = var.organization
+
+  network_provider = var.vdc_network_provider
+  provider_vdc     = var.vdc_provider_vdc
+
+  cpu_allocated  = var.vdc_cpu_allocated
+  cpu_guaranteed = var.vdc_cpu_guaranteed
+  mem_allocated  = var.vdc_mem_allocated
+
+  # JSON-массив дисковых политик (size в GB)
+  storage_config = var.vdc_storage_config
+
+  suspend_on_destroy = true
+}