[FEA]: Provide support for `<memory>` within libcu++

### Is this a duplicate?

- [X] I confirmed there appear to be no [duplicate issues](https://github.com/NVIDIA/cccl/issues) for this request and that I agree to the [Code of Conduct](CODE_OF_CONDUCT.md)

### Area

libcu++

### Is your feature request related to a problem? Please describe.

The `` header provides a lot of useful machinery that handles the non so subtle topic of memory allocation and handling of uninitialized memory.

To improve user experience we should implement this within libcu++ and also provide extensions that leverage e.g different memory categories that we have on device.

this depends on both #179 and #180

### Describe the solution you'd like

We should continue our modularization efforts here and see what extensions are suitable

### Describe alternatives you've considered

_No response_

### Additional context

_No response_