Add pybamm-cookie guides and references in the documentation

[santacodes]

As discussed in the 2024-09-02 Developer Meeting moving forward the template would be the way to add third-party parameter sets and models as it supports its entry points. This would require references in the documentation and guides on how to use the template and map entry points. In addition to that the documentation would also contain steps on how to package it to make it more accessible for the community to fetch it and run it locally out of the box.

P.S. I am happy to take up this issue so feel free to assign me if someone is not already working on it after the meeting.