Eig Rewrites

[tanish1729]

Description

Adds rewrites for eigenvalue eigenvector calculations

1. For identity matrix, all the eigenvalues are 1 and eigenvectors are standard basis
2. For diagonal matrix, the eigenvalues are the diagonal elements and the eigenvectors are the standard basis

Related Issue

• Related to ENH: Implement COLA library rewrites for linear algebra functions #573

Checklist

• Checked that the pre-commit linting/style checks pass
• Included tests that prove the fix is effective or that the new feature works
• Added necessary documentation (docstrings and/or example notebooks)
• If you are a pro: each commit corresponds to a relevant logical change

Type of change

• New feature / enhancement
• Bug fix
• Documentation
• Maintenance
• Other (please specify):

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📚 Documentation preview 📚: https://pytensor--1126.org.readthedocs.build/en/1126/

[codecov]

Codecov Report

Attention: Patch coverage is 93.93939% with 2 lines in your changes missing coverage. Please review.

Project coverage is 82.13%. Comparing base (231a977) to head (bdd1679).

Files with missing lines	Patch %	Lines
pytensor/tensor/rewriting/linalg.py	93.93%	1 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #1126      +/-   ##
==========================================
+ Coverage   82.10%   82.13%   +0.02%     
==========================================
  Files         185      185              
  Lines       48130    48163      +33     
  Branches     8669     8675       +6     
==========================================
+ Hits        39519    39558      +39     
+ Misses       6444     6439       -5     
+ Partials     2167     2166       -1     

Files with missing lines	Coverage Δ
pytensor/tensor/rewriting/linalg.py	92.85% <93.93%> (+0.09%)	⬆️

... and 2 files with indirect coverage changes