Bumps [codecov/codecov-action](https://github.com/codecov/codecov-action) from 3 to 4.
- [Release notes](https://github.com/codecov/codecov-action/releases)
- [Changelog](https://github.com/codecov/codecov-action/blob/main/CHANGELOG.md)
- [Commits](codecov/codecov-action@v3...v4)

---
updated-dependencies:
- dependency-name: codecov/codecov-action
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Bumps [dorny/paths-filter](https://github.com/dorny/paths-filter) from 3.0.1 to 3.0.2.
- [Release notes](https://github.com/dorny/paths-filter/releases)
- [Changelog](https://github.com/dorny/paths-filter/blob/master/CHANGELOG.md)
- [Commits](dorny/paths-filter@v3.0.1...v3.0.2)

---
updated-dependencies:
- dependency-name: dorny/paths-filter
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

…ML#1932)

* doc changes re at-functor and at-layer

* fix a doctest

* more fixes

* public at-layer

* add a sentence comparing to freeze/thaw

* Apply suggestions from code review

Co-authored-by: Kyle Daruwalla <daruwalla@wisc.edu>

* two fixes re SignDecay

---------

Co-authored-by: Kyle Daruwalla <daruwalla@wisc.edu>