File_Writer for DigitalSurf files

[Attolight-NTappy]

Description of the change

This PR implements save support for digitalsurf file formats:

• Implement file_writer for the digitalsurf formats (.sur and .pro)
• Correct a minor bug causing some datasets being offset by a constant upon loading
• Improve documentation

Progress of the PR

• [x] Change implemented (can be split into several points),
• [x] update docstring (if appropriate),
• [x] update user guide (if appropriate),
• [x] add a changelog entry in the upcoming_changes folder (see upcoming_changes/README.rst),
• [x] Check formatting of the changelog entry (and eventual user guide changes) in the docs/readthedocs.org:rosettasciio build of this PR (link in github checks)
• [x] add tests,
• [x] ready for review.

Minimal example of the bug fix or the new feature

import numpy as np
from rsciio.digitalsurf import file_writer,file_reader
md = { 'General': {},
       'Signal': {}}

ax  = {'name': 'X',
 'navigate': False,
 }

sd = {"data": np.arange(24)+111,
       "axes": [ax],
       "metadata": md,
       "original_metadata": {}}

file_writer("test.pro",sd)
file_reader('test.pro')[0]['data']
#array([111., 112., 113., 114., 115., 116., 117., 118., ... 133., 134.])

[codecov[bot]]

Codecov Report

Attention: Patch coverage is 97.51773% with 14 lines in your changes missing coverage. Please review.

Project coverage is 87.66%. Comparing base (e921e77) to head (1f5e4c5). Report is 32 commits behind head on main.

Files	Patch %	Lines
rsciio/digitalsurf/_api.py	97.50%	0 Missing and 14 partials :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #280 +/- ## ========================================== + Coverage 86.33% 87.66% +1.33% ========================================== Files 83 83 Lines 10672 11150 +478 Branches 2331 2414 +83 ========================================== + Hits 9214 9775 +561 + Misses 939 860 -79 + Partials 519 515 -4 ```

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[Attolight-NTappy]

This is now ready for review :)

[ericpre]

pre-commit.ci autofix

[Attolight-NTappy]

Thanks for review!

I made a few comments and maybe it would be good to increase the coverage? There are a couple of if block which are not coverage.

Alright, wait for it I'll push some new tests later today

[ericpre]

parse_metadata needs to be part of the public API, this is the test that needs to be updated to take into account this change.

[Attolight-NTappy]

Ok. I thought you would not consider changing this. Hadn't realized some other modules where already deviating from the file_reader,file_writer norm my bad

[Attolight-NTappy]

Ok finally I think we're there.

[ericpre]

Thank you @Attolight-NTappy, I push some tweaks to please ruff and improve the release note.

[Attolight-NTappy]

🤩