CHORE: SetupMaxwell refactoring to save fields and new SweepMaxwell for EC solvers

[gmalinve]

Description

**In this PR I want to:

• Improve the SetupMaxwell class in order to be able to save fields for all solvers.
• Add a new class in solve_sweep to handle EC freq. sweeps.
• Add/improve the already exisiting method to add frequency sweeps for EC in order to return the sweep object.**

Issue linked

Please mention the issue number or describe the problem this pull request addresses.

Checklist

• I have tested my changes locally.
• I have added necessary documentation or updated existing documentation.
• I have followed the coding style guidelines of this project.
• I have added appropriate tests (unit, integration, system).
• I have reviewed my changes before submitting this pull request.
• I have linked the issue or issues that are solved by the PR if any.
• I have agreed with the Contributor License Agreement (CLA).

[ansys-reviewer-bot]

Thanks for opening a Pull Request. If you want to perform a review write a comment saying:

@ansys-reviewer-bot review

[codecov]

Codecov Report

Attention: Patch coverage is 70.12987% with 46 lines in your changes missing coverage. Please review.

Project coverage is 83.72%. Comparing base (8214b24) to head (fdb45a8).
Report is 1 commits behind head on main.

❌ Your patch check has failed because the patch coverage (70.12%) is below the target coverage (85.00%). You can increase the patch coverage or adjust the target coverage.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #5670      +/-   ##
==========================================
- Coverage   85.20%   83.72%   -1.48%     
==========================================
  Files         156      156              
  Lines       61071    61194     +123     
==========================================
- Hits        52035    51235     -800     
- Misses       9036     9959     +923