[lie_closure2] Add `qml.dla.lie_closure` function

[Qottmann]

[WIP]

• [x] Basic functionality
• [x] Basic tests
• [x] compatibility with PauliWord + tests
• [x] compatibility with Operators + tests
• [ ] Figure out normalization standard
• [x] changelog

Follow-up on https://github.com/PennyLaneAI/pennylane/pull/5161 [sc-51421]

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 99.67%. Comparing base (d03216e) to head (b86ffaf). Report is 2 commits behind head on master.

Additional details and impacted files

@@           Coverage Diff            @@
##           master    #5169    +/-   ##
========================================
  Coverage   99.67%   99.67%            
========================================
  Files         407      409     +2     
  Lines       38019    37859   -160     
========================================
- Hits        37895    37737   -158     
+ Misses        124      122     -2     

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[trbromley]

Sorry for the delay in reviewing this @Qottmann, this week has been a bit busy. I'll try to get to this asap early next week, but feel free to ping me again.