Add RFT QC widget status column test

[HakonSohoel]

Issue
Resolves #14330

• 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 screenshots are changed: Review screenshot-PR in ert-testdata,
  merge screenshot-PR in ert-testdata before merging this PR.
• 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')

[HakonSohoel]

Created the test to see if the rft qc widget was affected by a polars bug (#14277 (comment)). It turned out it was not affected, but this test still verifies that the response status column is added as expected both with and without response approximation, so it is worth keeping.

[codecov-commenter]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 70.55%. Comparing base (4e36dd4) to head (1219c31).
⚠️ Report is 8 commits behind head on main.

❗ There is a different number of reports uploaded between BASE (4e36dd4) and HEAD (1219c31). Click for more details.

HEAD has 13 uploads less than BASE

Flag	BASE (4e36dd4)	HEAD (1219c31)
gui-tests	4	2
test	4	2
fuzz	3	2
performance-and-unit-tests	4	0
cli-tests	4	0

Additional details and impacted files

@@             Coverage Diff             @@
##             main   #14355       +/-   ##
===========================================
- Coverage   91.75%   70.55%   -21.21%     
===========================================
  Files         485      497       +12     
  Lines       34708    36062     +1354     
===========================================
- Hits        31848    25444     -6404     
- Misses       2860    10618     +7758     

Flag	Coverage Δ
cli-tests	?
fuzz	43.85% <ø> (-0.04%)	⬇️
gui-tests	58.04% <ø> (-0.14%)	⬇️
performance-and-unit-tests	?
test	45.27% <ø> (-0.02%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.
see 266 files with indirect coverage changes

[codspeed-hq]

Merging this PR will not alter performance

✅ 36 untouched benchmarks

---

_{Comparing HakonSohoel:add-rft-status-column-test (1219c31) with main (112f2c8)}

[achaikou]

⭐ 👍

[achaikou]

Just a note:

To keep schemas consistent with possible future changes might be useful to use
defaults_generator's create_rft_observation + create_observation_dataframe's _handle_rft_observation (or just add new create_rft_observation_dataframe function to defaults_generator)

Also might be nice adding create_rft_response consistent with default rft observations (in the lines of create_seismic_response) to use standard response schema and get rid of explicitly defining uninteresting defaults like well-date-pressure.