# Description
This PR breaks the actuator config into separate files in order to avoid
a circular import which arises once the configuration is imported into
the actuator base class for more than type hinting.


## Type of change
- Possible breaking change! The actuator configs have moved `.py` files
and thus modules. They can still be imported directly from the
`isaaclab.actuators` package. External references to these classes
through the `actuator_cfg` module will not longer work. Instead, import
directly from the `isaaclab.actuators` package.

## Checklist

- [x] I have read and understood the [contribution
guidelines](https://isaac-sim.github.io/IsaacLab/main/source/refs/contributing.html)
- [x] I have run the [`pre-commit` checks](https://pre-commit.com/) with
`./isaaclab.sh --format`
- [x] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [x] I have added tests that prove my fix is effective or that my
feature works
- [x] I have updated the changelog and the corresponding version in the
extension's `config/extension.toml` file
- [x] I have added my name to the `CONTRIBUTORS.md` or my name already
exists there

---------
Signed-off-by: Brian McCann <144816553+bmccann-bdai@users.noreply.github.com>
Signed-off-by: Kelly Guo <kellyg@nvidia.com>
Co-authored-by: greptile-apps[bot] <165735046+greptile-apps[bot]@users.noreply.github.com>
Co-authored-by: Kelly Guo <kellyg@nvidia.com>