Improved the xTB parser

[alongd]

No description provided.

[Copilot]

Pull request overview

This PR improves ARC’s xTB parsing behavior and strengthens regression coverage for common xTB log output edge cases.

Changes:

• Fix xTB 1D scan angle generation so returned angles and energies lengths match.
• Improve xTB parsing robustness for frequencies (use last eigval block), ZPE parsing (regex), energy parsing (avoid “total energy gain” false match), geometry parsing (reset on new blocks), and basic error detection.
• Add targeted unit tests covering the above xTB-specific behaviors.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
arc/parser/parser_test.py	Updates 1D scan expectations and adds xTB-focused regression tests for energy/frequency/ZPE/geometry/error detection.
arc/parser/adapters/xtb.py	Implements xTB parser robustness improvements (error detection, geometry block reset, eigval-block selection, regex parsing, angle-length fix).

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.09%. Comparing base (5c50f88) to head (960197e).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #856      +/-   ##
==========================================
+ Coverage   60.08%   60.09%   +0.01%     
==========================================
  Files         102      102              
  Lines       31041    31045       +4     
  Branches     8082     8087       +5     
==========================================
+ Hits        18651    18658       +7     
+ Misses      10076    10071       -5     
- Partials     2314     2316       +2     

Flag	Coverage Δ
functionaltests	60.09% <ø> (+0.01%)	⬆️
unittests	60.09% <ø> (+0.01%)	⬆️

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