feat(imagebuilder-alpha): add support for Distribution Configuration Construct (#36005)

### Issue #

aws/aws-cdk-rfcs#789

### Reason for this change

This change adds a new alpha module for EC2 Image Builder L2 Constructs (`@aws-cdk/aws-imagebuilder-alpha`), as outlined in aws/aws-cdk-rfcs#789. This PR specifically implements the `DistributionConfiguration` construct.

### Description of changes

This change implements the `DistributionConfiguration` construct, which is a higher-level construct of [`CfnDistributionConfiguration`](https://docs.aws.amazon.com/cdk/api/v2/docs/aws-cdk-lib.aws_imagebuilder.CfnDistributionConfiguration.html).

#### Example

```ts
const distributionConfiguration = new imagebuilder.DistributionConfiguration(this, 'DistributionConfiguration', {
  distributionConfigurationName: 'test-distribution-configuration',
  description: 'A Distribution Configuration',
  amiDistributions: [
    {
      // Distribute AMI to us-east-2 and publish the AMI ID to an SSM parameter
      region: 'us-east-2',
      ssmParameters: [
        {
          parameter: ssm.StringParameter.fromStringParameterAttributes(this, 'CrossRegionParameter', {
            parameterName: '/imagebuilder/ami',
            forceDynamicReference: true
          })
        }
      ]
    }
  ]
});

// For AMI-based image builds - add an AMI distribution in the current region
distributionConfiguration.addAmiDistributions({
  amiName: 'imagebuilder-{{ imagebuilder:buildDate }}',
  amiDescription: 'Build AMI',
  amiKmsKey: kms.Key.fromLookup(this, 'ComponentKey', { aliasName: 'alias/distribution-encryption-key' }),
  // Copy the AMI to different accounts
  amiTargetAccountIds: ['123456789012', '098765432109'],
  // Add launch permissions on the AMI
  amiLaunchPermission: {
    organizationArns: [
      this.formatArn({ region: '', service: 'organizations', resource: 'organization', resourceName: 'o-1234567abc' })
    ],
    organizationalUnitArns: [
      this.formatArn({
        region: '',
        service: 'organizations',
        resource: 'ou',
        resourceName: 'o-1234567abc/ou-a123-b4567890'
      })
    ],
    userGroups: ['all'],
    userIds: ['234567890123']
  },
  // Attach tags to the AMI
  amiTags: {
    Environment: 'production',
    Version: '{{ imagebuilder:buildVersion }}'
  },
  // Optional - publish the distributed AMI ID to an SSM parameter
  ssmParameters: [
    {
      parameter: ssm.StringParameter.fromStringParameterAttributes(this, 'Parameter', {
        parameterName: '/imagebuilder/ami',
        forceDynamicReference: true
      })
    },
    {
      amiAccount: '098765432109',
      dataType: ssm.ParameterDataType.TEXT,
      parameter: ssm.StringParameter.fromStringParameterAttributes(this, 'CrossAccountParameter', {
        parameterName: 'imagebuilder-prod-ami',
        forceDynamicReference: true
      })
    }
  ],
  // Optional - create a new launch template version with the distributed AMI ID
  launchTemplates: [
    {
      launchTemplate: ec2.LaunchTemplate.fromLaunchTemplateAttributes(this, 'LaunchTemplate', {
        launchTemplateName: 'imagebuilder-ami'
      }),
      setDefaultVersion: true
    },
    {
      accountId: '098765432109',
      launchTemplate: ec2.LaunchTemplate.fromLaunchTemplateAttributes(this, 'CrossAccountLaunchTemplate', {
        launchTemplateName: 'imagebuilder-cross-account-ami'
      }),
      setDefaultVersion: true
    }
  ],
  // Optional - enable Fast Launch on an imported launch template
  fastLaunchConfigurations: [
    {
      enabled: true,
      launchTemplate: ec2.LaunchTemplate.fromLaunchTemplateAttributes(this, 'FastLaunchLT', {
        launchTemplateName: 'fast-launch-lt'
      }),
      maxParallelLaunches: 10,
      targetSnapshotCount: 2
    }
  ],
  // Optional - license configurations to apply to the AMI
  licenseConfigurationArns: [
    'arn:aws:license-manager:us-west-2:123456789012:license-configuration:lic-abcdefghijklmnopqrstuvwxyz'
  ]
});
```

### Describe any new or updated permissions being added

N/A - new L2 construct in alpha module

### Description of how you validated changes

Validated with unit tests and integration tests. Manually verified generated CFN templates as well.

### Checklist
- [x] My code adheres to the [CONTRIBUTING GUIDE](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md) and [DESIGN GUIDELINES](https://github.com/aws/aws-cdk/blob/main/docs/DESIGN_GUIDELINES.md)

----

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: tarunb12

packages/@aws-cdk/aws-imagebuilder-alpha/README.md

@@ -296,3 +296,110 @@ const infrastructureConfiguration = new imagebuilder.InfrastructureConfiguration
   }
 });
 ```
+
+### Distribution Configuration
+
+Distribution configuration defines how and where your built images are distributed after successful creation. For AMIs,
+this includes target AWS Regions, KMS encryption keys, account sharing permissions, License Manager associations, and
+launch template configurations. For container images, it specifies the target Amazon ECR repositories across regions.
+A distribution configuration can be associated with an image or an image pipeline to define these distribution settings
+for image builds.
+
+```ts
+const distributionConfiguration = new imagebuilder.DistributionConfiguration(this, 'DistributionConfiguration', {
+  distributionConfigurationName: 'test-distribution-configuration',
+  description: 'A Distribution Configuration',
+  amiDistributions: [
+    {
+      // Distribute AMI to us-east-2 and publish the AMI ID to an SSM parameter
+      region: 'us-east-2',
+      ssmParameters: [
+        {
+          parameter: ssm.StringParameter.fromStringParameterAttributes(this, 'CrossRegionParameter', {
+            parameterName: '/imagebuilder/ami',
+            forceDynamicReference: true
+          })
+        }
+      ]
+    }
+  ]
+});
+
+// For AMI-based image builds - add an AMI distribution in the current region
+distributionConfiguration.addAmiDistributions({
+  amiName: 'imagebuilder-{{ imagebuilder:buildDate }}',
+  amiDescription: 'Build AMI',
+  amiKmsKey: kms.Key.fromLookup(this, 'ComponentKey', { aliasName: 'alias/distribution-encryption-key' }),
+  // Copy the AMI to different accounts
+  amiTargetAccountIds: ['123456789012', '098765432109'],
+  // Add launch permissions on the AMI
+  amiLaunchPermission: {
+    organizationArns: [
+      this.formatArn({ region: '', service: 'organizations', resource: 'organization', resourceName: 'o-1234567abc' })
+    ],
+    organizationalUnitArns: [
+      this.formatArn({
+        region: '',
+        service: 'organizations',
+        resource: 'ou',
+        resourceName: 'o-1234567abc/ou-a123-b4567890'
+      })
+    ],
+    isPublicUserGroup: true,
+    accountIds: ['234567890123']
+  },
+  // Attach tags to the AMI
+  amiTags: {
+    Environment: 'production',
+    Version: '{{ imagebuilder:buildVersion }}'
+  },
+  // Optional - publish the distributed AMI ID to an SSM parameter
+  ssmParameters: [
+    {
+      parameter: ssm.StringParameter.fromStringParameterAttributes(this, 'Parameter', {
+        parameterName: '/imagebuilder/ami',
+        forceDynamicReference: true
+      })
+    },
+    {
+      amiAccount: '098765432109',
+      dataType: ssm.ParameterDataType.TEXT,
+      parameter: ssm.StringParameter.fromStringParameterAttributes(this, 'CrossAccountParameter', {
+        parameterName: 'imagebuilder-prod-ami',
+        forceDynamicReference: true
+      })
+    }
+  ],
+  // Optional - create a new launch template version with the distributed AMI ID
+  launchTemplates: [
+    {
+      launchTemplate: ec2.LaunchTemplate.fromLaunchTemplateAttributes(this, 'LaunchTemplate', {
+        launchTemplateId: 'lt-1234'
+      }),
+      setDefaultVersion: true
+    },
+    {
+      accountId: '123456789012',
+      launchTemplate: ec2.LaunchTemplate.fromLaunchTemplateAttributes(this, 'CrossAccountLaunchTemplate', {
+        launchTemplateId: 'lt-5678'
+      }),
+      setDefaultVersion: true
+    }
+  ],
+  // Optional - enable Fast Launch on an imported launch template
+  fastLaunchConfigurations: [
+    {
+      enabled: true,
+      launchTemplate: ec2.LaunchTemplate.fromLaunchTemplateAttributes(this, 'FastLaunchLT', {
+        launchTemplateName: 'fast-launch-lt'
+      }),
+      maxParallelLaunches: 10,
+      targetSnapshotCount: 2
+    }
+  ],
+  // Optional - license configurations to apply to the AMI
+  licenseConfigurationArns: [
+    'arn:aws:license-manager:us-west-2:123456789012:license-configuration:lic-abcdefghijklmnopqrstuvwxyz'
+  ]
+});
+```