feat(enterprises): Enterprise role binding resource (#580)

# Enterprise Role Bindings Resource

## Overview
This PR introduces the `castai_enterprise_role_binding` resource for managing enterprise role bindings in CAST AI, enabling programmatic access control across organizations.

## Features
- **Full Lifecycle Management**: Create, read, update, and delete operations for role bindings
- **Enterprise Context**: Manage role assignments at enterprise and organization levels
- **Multi-Subject Support**: Assign roles to users, service accounts, and groups
- **Batch Operations**: Efficient API calls for managing multiple bindings

## Key Capabilities
- Scoped role assignment with organization-level granularity
- Support for multiple subject types (users, service accounts, groups)
- Infrastructure-as-code approach for RBAC management
- Version-controlled access policies with audit trails

## Implementation
- **Changes**: 2,748 additions, 3 deletions
- **Status**: Approved by radekska
- **API Integration**: Uses Enterprise API batch operations for create, read, update, and delete

## Use Cases
- Define enterprise access policies as infrastructure
- Automate service account provisioning for CI/CD
- Implement hierarchical RBAC across organizations
- Maintain audit trails for compliance

Author: 0msokolowski0

castai/provider.go

@@ -66,6 +66,7 @@ func Provider(version string) *schema.Provider {
 			"castai_security_runtime_rule":         resourceSecurityRuntimeRule(),
 			"castai_allocation_group":              resourceAllocationGroup(),
 			"castai_enterprise_group":              resourceEnterpriseGroup(),
+			"castai_enterprise_role_binding":       resourceEnterpriseRoleBinding(),
 		},
 
 		DataSourcesMap: map[string]*schema.Resource{

castai/resource_eks_cluster_userarn.go

@@ -17,7 +17,7 @@ func resourceEKSClusterUserARN() *schema.Resource {
 		ReadContext:   resourceEKSUserARNRead,
 		CreateContext: resourceEKSUserARNCreate,
 		DeleteContext: resourceEKSUserARNDelete,
-		Description: "Retrieve EKS Cluster User ARN",
+		Description:   "Retrieve EKS Cluster User ARN",
 		Schema: map[string]*schema.Schema{
 			EKSClusterUserARNFieldClusterID: {
 				Type:             schema.TypeString,

castai/resource_enterprise_group_test.go

@@ -272,7 +272,7 @@ func TestResourceEnterpriseGroupCreateContext(t *testing.T) {
 							ManagedBy:      "terraform",
 							CreateTime:     createTime,
 							OrganizationId: organizationID,
-							Status:       []organization_management.RoleBindingRoleBindingStatus{},
+							Status:         []organization_management.RoleBindingRoleBindingStatus{},
 							Definition: organization_management.RoleBindingRoleBindingDefinition{
 								RoleId: roleID3,
 								Scopes: &[]organization_management.Scope{