Mention GAMS and GAMSPy in third-party modeling languages page in documentation

[0x17]

Description

This PR adds a mention of the GAMS and GAMSPy solver link for cuOpt.

I created this as a draft, as the PR has some prerequisites:

• The repository for the solver link cuoptlink-builder must be set to public beforehand and this will be timed with the publication of a GAMS blog article on the link.
• A counterpart PR for the cuopt-examples repository should ideally be merged shortly before as it is mentioned here.

Issue

Part of resolving #188

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[rgsl888prabhu]

Thank you @0x17 for the PR,

Please also update these pages as well

https://github.com/NVIDIA/cuopt/blob/branch-25.08/docs/cuopt/source/introduction.rst
https://github.com/NVIDIA/cuopt/blob/branch-25.08/docs/cuopt/source/lp-features.rst
https://github.com/NVIDIA/cuopt/blob/branch-25.08/docs/cuopt/source/milp-features.rst

[0x17]

Please also update these pages as well ...

Thanks for the hint @rgsl888prabhu. I now did so via commit 0f3c060.

[rgsl888prabhu]

/ok to test 0f3c060

[0x17]

The link has now been made public https://github.com/GAMS-dev/cuoptlink-builder.

[rgsl888prabhu]

Thank you @0x17 I will rerun the CI and merge it.

[rgsl888prabhu]

/ok to test 86f7da2

[rgsl888prabhu]

/ok to test e1cbd05

[rgsl888prabhu]

/merge