[Feature request] - Add the possibility to dump the photon source to SDEF or CDGS

[dodu94]

Is your feature request related to a problem? Please describe.
It would be useful to dump the computed photon source to SDEF or CDGS format in order to run the photon transport in MCNP where the effects of geometry can be taken into account

Describe the solution you'd like
An additional input parameter should be added which controls the dumping of the photon source

[Radiation-Transport]

Please have a look at the following repo: https://github.com/marco-de-pietri/mcflow/blob/main/src/mcflow/pipes_cdgs.py