Combine datasets & refactor observations to response configs

[yngve-sk]

squash of https://github.com/equinor/ert/pull/7495

Requires change in semeio: https://github.com/equinor/semeio/pull/609

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 93.44262% with 56 lines in your changes are missing coverage. Please review.

Project coverage is 85.90%. Comparing base (140e5d7) to head (b2a7932). Report is 8 commits behind head on main.

Files	Patch %	Lines
src/ert/storage/local_ensemble.py	95.73%	11 Missing :warning:
src/ert/storage/migration/to6.py	90.69%	8 Missing :warning:
src/ert/config/observations.py	90.00%	7 Missing :warning:
src/ert/libres_facade.py	40.00%	6 Missing :warning:
src/ert/config/summary_config.py	94.18%	5 Missing :warning:
src/ert/config/obs_commons.py	94.02%	4 Missing :warning:
src/ert/dark_storage/common.py	90.69%	4 Missing :warning:
src/ert/dark_storage/endpoints/records.py	71.42%	4 Missing :warning:
src/ert/config/gen_data_config.py	95.83%	3 Missing :warning:
src/ert/config/commons.py	94.44%	1 Missing :warning:
... and 3 more

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7563      +/-   ##
==========================================
+ Coverage   85.76%   85.90%   +0.13%     
==========================================
  Files         379      381       +2     
  Lines       23117    23441     +324     
  Branches      624      630       +6     
==========================================
+ Hits        19827    20136     +309     
- Misses       3209     3232      +23     
+ Partials       81       73       -8     

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[yngve-sk]

Known issues 2fix:

• Combination is not done after final iteration the way it is done now, due to no update
• (On local MacOS M1) Running performance_utils example takes about 1h20min, combining datasets about 10mins per iteration (being with 200 * 3400 gen_data entries, and 200 summary files at 1.6MB each). Memory usage at most around 1.8GB during the update.

[eivindjahren]

closes #5065