Use datamod for scale action configuration

[tweska]

Required support for parsing vectors of subconfigurations (MUL-291).

🌈🌦️📖🚧 Documentation 🚧📖🌦️🌈
https://sites.ecmwf.int/docs/dev-section/multio/pull-requests/PR-160

[codecov-commenter]

Codecov Report

❌ Patch coverage is 87.23404% with 6 lines in your changes missing coverage. Please review.
✅ Project coverage is 56.65%. Comparing base (2450a3a) to head (43fe507).

Files with missing lines	Patch %	Lines
src/multio/action/scale/Scale.h	44.44%	5 Missing ⚠️
src/multio/datamod/core/NestedRecord.h	85.71%	1 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop     #160      +/-   ##
===========================================
+ Coverage    56.62%   56.65%   +0.02%     
===========================================
  Files          318      320       +2     
  Lines        20649    20674      +25     
  Branches      1570     1574       +4     
===========================================
+ Hits         11693    11713      +20     
- Misses        8956     8961       +5     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

[pgeier]

A few minor changes are needed.

[MircoValentiniECMWF]

I recommend limiting datamod to the encoder for now. Until it is stable and merged into metkit, wider adoption will likely introduce breaking changes, requiring manual adaptation of all actions. I see this as very dangerous.