feat: add C implementation for stats/base/dists/erlang/cdf

[rautelaKamal]

Description

What is the purpose of this pull request?

This pull request adds a C implementation for evaluating the cumulative distribution function (CDF) of an Erlang distribution (@stdlib/stats/base/dists/erlang/cdf). The implementation validates that the shape parameter k is a non-negative integer and delegates to the existing stdlib_base_dists_gamma_cdf function.

Related Issues

Does this pull request have any related issues?

This pull request has the following related issues:

• [RFC]: Add C implementation for @stdlib/stats/base/dists/erlang/cdf #3568

Questions

Any questions for reviewers of this pull request?

No.

Other

Any other information relevant to this pull request? This may include screenshots, references, and/or implementation notes.

No.

Checklist

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

• Read, understood, and followed the contributing guidelines.

AI Assistance

When authoring the changes proposed in this PR, did you use any kind of AI assistance?

• Yes
• No

If you answered "yes" above, how did you use AI assistance?

• Code generation (e.g., when writing an implementation or fixing a bug)
• Test/benchmark generation
• Documentation (including examples)
• Research and understanding

Disclosure

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