feat: add C implementation for `math/base/special/riemann-zeta`

[gunjjoshi]

Description

What is the purpose of this pull request?

This pull request:

• adds C implementation for math/base/special/riemann-zeta.

double stdlib_base_zeta( const double s );

Related Issues

Does this pull request have any related issues?

This pull request:

• resolves a part of #649.

Questions

Any questions for reviewers of this pull request?

No.

Other

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No.

Checklist

Please ensure the following tasks are completed before submitting this pull request.

• [x] Read, understood, and followed the contributing guidelines.

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