Move copy_parameters to LocalEnsemble

[xjules]

Issue
Further simplification of ParameterConfig API

Approach
move copy_parameters into the LocalEnsemble

(Screenshot of new behavior in GUI if applicable)

• PR title captures the intent of the changes, and is fitting for release notes.
• Added appropriate release note label
• Commit history is consistent and clean, in line with the contribution guidelines.
• Make sure unit tests pass locally after every commit (git rebase -i main --exec 'just rapid-tests')

When applicable

• When there are user facing changes: Updated documentation
• New behavior or changes to existing untested code: Ensured that unit tests are added (See Ground Rules).
• Large PR: Prepare changes in small commits for more convenient review
• Bug fix: Add regression test for the bug
• Bug fix: Add backport label to latest release (format: 'backport release-branch-name')

[codspeed-hq]

CodSpeed Performance Report

Merging #11500 will not alter performance

_{Comparing xjules:copy_params (f1eb32e) with main (8a2a793)}

Summary

✅ 22 untouched benchmarks

[dafeda]

Why is it better to have this function be part of the ensemble and not the experiment?

Edit: I actually quite like this :)

[dafeda]

Nice

[xjules]

Nice

Thanks! We will wait with this one a bit since we might remove the group names and use the data files as a grouping of parameters instead.