[FEA]: Support `block_aggregate` in python cuda_cooperative.block.exclusive_sum

### Is this a duplicate?

- [ ] 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

Thrust

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

there seems to be a small missmatch with cub, it would be great if the function could return the aggregated sum together.

https://github.com/dmlc/cub/blob/master/cub/block/block_scan.cuh#L383

### Describe the solution you'd like

Add another parameter to the scan functions to return the aggregated value.

### Describe alternatives you've considered

_No response_

### Additional context

_No response_