Feat: add vacancy formation task

[anyangml]

This PR add a new property calculation task.

[Copilot]

Pull Request Overview

This PR introduces a new property calculation task for vacancy formation energy in inorganic materials. The implementation evaluates models' ability to predict the energy required to form oxygen vacancies in crystal structures.

Key Changes:

• Added vacancy formation energy calculation task with oxygen reference energy computation
• Integrated the new task into the evaluation pipeline with appropriate metrics
• Configured test data path and evaluation parameters

Reviewed Changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

Show a summary per file

File	Description
lambench/tasks/calculator/vacancy/vacancy.py	Core implementation of vacancy formation energy calculation with O2 reference energy
lambench/tasks/calculator/calculator_tasks.yml	Configuration entry for the vacancy task with test data path
lambench/models/ase_models.py	Integration of vacancy task into the ASEModel evaluation flow
lambench/metrics/post_process.py	Added vacancy to the list of domain-specific tasks for post-processing
lambench/metrics/downstream_tasks_metrics.yml	Defined metrics and dummy baseline for vacancy task evaluation

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[codecov]

Codecov Report

❌ Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 65.72%. Comparing base (063ad5e) to head (1a8310f).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
lambench/models/ase_models.py	0.00%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #370      +/-   ##
==========================================
- Coverage   65.89%   65.72%   -0.17%     
==========================================
  Files          35       35              
  Lines        1589     1593       +4     
  Branches      189      190       +1     
==========================================
  Hits         1047     1047              
- Misses        500      504       +4     
  Partials       42       42              

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[Copilot]

Pull Request Overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 3 comments.

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