feat: restored sis

[ThomasPiellard]

Description

Cleaned SIS code and templates, and added test cases for babybear, koalabear and goldilocks.

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How has this been tested?

Please describe the tests that you ran or implemented to verify your changes. Provide instructions so we can reproduce.

See the test suite in the sis/ folders.

How has this been benchmarked?

Please describe the benchmarks that you ran to verify your changes.

See the benchmarks in the sis/ folders.

Checklist:

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my fix is effective or that my feature works
• I did not modify files generated from templates
• golangci-lint does not output errors locally
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules