Allow using a CSV file to define currents for hydrodynamic system

[arjo129]

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🎉 New feature

Closes #

Summary

This PR adds support for looking up hydrodynamic currents from a data file via the new Environment component. This allows users to vary currents throughout the water column.

Adds the tags:

        <lookup_current_x>current_x</lookup_current_x>
        <lookup_current_y>current_y</lookup_current_y>
        <lookup_current_z>current_z</lookup_current_z>

When present, they use the tag to look up current from the Environment component. If one is not present, that column defaults to zero.

Signed-off-by: Arjo Chakravarty arjo@openrobotics.org

Test it

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• Consider updating Python bindings (if the library has them)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[hidmic]

First pass. Code formatting is a bit odd but otherwise it's looking good.

[hidmic]

Second pass. Looking good!