Fix hypoelastic probe output

[ChrisZYJ]

Description

• Bug fix

Fix hypoelastic probe output (tau_e):
Previously 1D probes drop the computed tau_e(1), 3D probes contain no stress, and the probe sound speed is acoustic-only

Testing

Passed local tests.

Checklist

Check these like this [x] to indicate which of the below applies.

• I added or updated tests for new behavior
• I updated documentation if user-facing behavior changed

See the developer guide for full coding standards.

GPU changes (expand if you modified src/simulation/)

• GPU results match CPU results
• Tested on NVIDIA GPU or AMD GPU

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 12 lines in your changes missing coverage. Please review.
✅ Project coverage is 61.18%. Comparing base (ae4b4c4) to head (6fe3f34).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/simulation/m_data_output.fpp	0.00%	12 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1721      +/-   ##
==========================================
- Coverage   61.21%   61.18%   -0.04%     
==========================================
  Files          84       84              
  Lines       21601    21612      +11     
  Branches     3195     3200       +5     
==========================================
  Hits        13223    13223              
- Misses       6209     6220      +11     
  Partials     2169     2169              

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