More robust export of interrupted datasets

[jenshnielsen]

Where setpoints are shared between multiple parameters

[Copilot]

Pull request overview

Improves QCoDeS xarray export robustness for incomplete/shape-mismatched measurements where shared setpoints can be represented inconsistently across per-parameter sub-datasets.

Changes:

• Normalize coord-vs-data_var role conflicts across sub-datasets before calling xr.merge to avoid xarray MergeError.
• Add a regression test covering an interrupted measurement with a shared setpoint that previously failed during to_xarray_dataset().

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
src/qcodes/dataset/exporters/export_to_xarray.py	Promotes conflicting variables to coordinates across all sub-datasets prior to merging, preventing coord/data_var ambiguity in xr.merge.
tests/dataset/test_dataset_export.py	Adds a regression test reproducing the shared-setpoint merge failure on incomplete measurements.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.56%. Comparing base (ffa18e5) to head (59ecf74).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7960      +/-   ##
==========================================
+ Coverage   60.54%   60.56%   +0.01%     
==========================================
  Files         333      333              
  Lines       32232    32243      +11     
==========================================
+ Hits        19516    19527      +11     
  Misses      12716    12716              

☔ 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.