Add support to "Activate AWS user-defined 'cost allocation tags' programmatically"

### Describe the feature

I would like to have a feature to "activate" the user-defined cost allocation tags programmatically.
Unless I can't find it, there doesn't appear to be an available AWS API method

### Use Case

Whenever I want to activate the user-defined cost allocation tags, I need to log into my payer account and manually click a button or two to activate the tags.
This seems like a glaringly obvious shortcoming.

I would like to have a feature, where I could maintain / activate the cost-allocation-tags programmatically

### Proposed Solution

_No response_

### Other Information

_No response_

### Acknowledgements

- [ ] I may be able to implement this feature request
- [ ] This feature might incur a breaking change

### CDK version used

v2

### Environment details (OS name and version, etc.)

mac os, rhel 8

No files, tests, or entry points are named. Start by verifying whether AWS exposes an API for activating user-defined cost allocation tags and how AWS CDK v2 represents that capability. Done means providing a supported programmatic way to activate the tags, with the relevant validation and documentation.

Written by the indexing model from the issue text.