Break down monolithic driver and heuristics tests

[alongd]

Splits the catch-all test_map_abstractions and heuristics tests into one test per reaction case, so failures point at a specific scenario instead of one giant test. Shared XYZ fixtures live on setUpClass. No production-code changes.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 60.45%. Comparing base (0f5d3ad) to head (5fe55b2).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #881   +/-   ##
=======================================
  Coverage   60.44%   60.45%           
=======================================
  Files         102      102           
  Lines       31096    31096           
  Branches     8103     8103           
=======================================
+ Hits        18796    18798    +2     
+ Misses       9957     9956    -1     
+ Partials     2343     2342    -1     

Flag	Coverage Δ
functionaltests	60.45% <ø> (+<0.01%)	⬆️
unittests	60.45% <ø> (+<0.01%)	⬆️

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[Copilot]

Pull request overview

This PR refactors ARC’s unit tests to improve failure granularity by splitting previously monolithic mapping-driver and heuristics tests into smaller, scenario-specific test cases. This makes it easier to identify which specific reaction case/regression is responsible when a test fails, without changing production behavior.

Changes:

• Split test_map_abstractions into multiple focused test methods, with shared XYZ fixtures moved to setUpClass.
• Split combined hydrolysis heuristics coverage into three dedicated tests (carbonyl-based, ether, nitrile), using separate per-test project directories.
• Refactor are_h_abs_wells_reversed coverage into multiple targeted tests using a shared assertion helper; expand teardown cleanup to remove the new test directories.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
arc/mapping/driver_test.py	Breaks up mapping abstraction cases into individual tests and centralizes shared XYZ fixtures in setUpClass.
arc/job/adapters/ts/heuristics_test.py	Splits hydrolysis heuristics tests by family, refactors H-abstraction well-orientation assertions into a helper + per-scenario tests, and updates teardown cleanup for new directories.

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[ranbenayoun]

Looks good to me