refactor: Use UUID for UniqueID

[JakubValtar]

This PR switches UniqueID to use UUID internally. This ensures uniqueness and preserves the ability to generate new unique IDs even after deserialization.

@wence- This changes the Python IR interface. The Cache::id_ field changes from usize to u128 since the ids now use 128 bits. I bumped the VERSION.

Closes #23674

[JakubValtar]

note: The main changes are in this file.

[JakubValtar]

note: The Python IR interface change is here.

[ritchie46]

The lowerhex isn't important. Normal print should be fine.

[codecov]

Codecov Report

Attention: Patch coverage is 77.77778% with 6 lines in your changes missing coverage. Please review.

Project coverage is 81.29%. Comparing base (72e9513) to head (a2556e7).
Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/polars-utils/src/unique_id.rs	60.00%	2 Missing ⚠️
crates/polars-plan/src/plans/ir/dot.rs	0.00%	1 Missing ⚠️
crates/polars-plan/src/plans/ir/tree_format.rs	0.00%	1 Missing ⚠️
...s-plan/src/plans/optimizer/collapse_and_project.rs	0.00%	1 Missing ⚠️
...rates/polars-python/src/lazyframe/visitor/nodes.rs	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #23704      +/-   ##
==========================================
+ Coverage   81.25%   81.29%   +0.03%     
==========================================
  Files        1644     1644              
  Lines      223318   223250      -68     
  Branches     2841     2841              
==========================================
+ Hits       181452   181481      +29     
+ Misses      41167    41070      -97     
  Partials      699      699              

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