Add new FromData operation description

[laggui]

Checklist

• Confirmed that run-checks all script has been executed.

Related Issues/PRs

Fixes #2719

Changes

• Added a new operation description for FromData, similar to other tensor creation ops (zeros, random, etc.)
• Refactored fusion to use the FromData description (fixes linked issue, since an operation is registered the handles are correctly freed)
• Fixed empty tensor op in fusion in the process (same issue as from data)

[codecov]

Codecov Report

Attention: Patch coverage is 98.94180% with 2 lines in your changes missing coverage. Please review.

Project coverage is 83.56%. Comparing base (b33bd24) to head (99b5fbe).
Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/burn-tensor/src/repr/operation.rs	60.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2735      +/-   ##
==========================================
- Coverage   83.59%   83.56%   -0.04%     
==========================================
  Files         819      824       +5     
  Lines      106600   108377    +1777     
==========================================
+ Hits        89113    90564    +1451     
- Misses      17487    17813     +326     

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