Adopt strict SurrogatesBase API QA

[ChrisRackauckas-Claude]

Ignore until reviewed by @ChrisRackauckas.

Summary

• Require SciMLTesting 2.4 and make the QA entrypoint exactly run_qa(SurrogatesBase).
• Remove QA-specific JET frame ignores and unused QA dependencies.
• Document every exported binding at its definition site using SciMLStyle sections, including concrete extension rules and examples.
• Render the module and all public API docs, enable export checkdocs, and add a developer interface guide.
• Add mock-only deterministic and stochastic extension-contract tests driven through public SurrogatesBase functions.
• Remove docs asset-copy plumbing and replace the rate-limited GitHub ColPrac README link with the canonical ColPrac documentation URL.

Validation

• Julia 1.12 Pkg.test()
• test/developer_interfaces.jl: 10/10 assertions
• strict plain run_qa(SurrogatesBase): 20/20
• Documenter doctests, export checkdocs, linkcheck, and HTML render
• Runic --check src test docs
• git diff --check
• direct export/docstring audit

Baseline investigation

The original documentation build fails identically on clean origin/main because GitHub returns HTTP 429 for the existing ColPrac README URL. This PR replaces that source link with https://docs.sciml.ai/ColPrac/stable/; no linkcheck setting was relaxed.