[FEA]: optimize the case of storing a `resource_ref` in an `any_resource`

### 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.

with the current implementation, storing a `cuda::rm::resource_ref` in a `cuda::experimental::any_resource` will double- type erase the underlying type, leading to double indirections for every function call.

### Describe the solution you'd like

find a way to bring this scenario down to a single indirection per type-erased function call.

### Describe alternatives you've considered

_No response_

### Additional context

_No response_