Raw numexpr engine

[jpn--]

This pull request includes several enhancements and bug fixes in the sharrow/relationships.py and sharrow/tree_branch.py files. The most important changes include adding a new CachedTree class, updating the get_expr method to support a new pandas-numexpr engine, and improving the eval method to handle numeric values.

Enhancements:

• New Class Addition:

  • Added CachedTree class to cache the results of getitem calls in sharrow/tree_branch.py.

• Method Updates:

  • Updated get_expr method in sharrow/relationships.py to support a new pandas-numexpr engine and added a parser argument for better expression evaluation. [1] [2] [3]
  • Enhanced eval method in sharrow/relationships.py to handle numeric values and booleans, broadcasting them appropriately to the root dimensions.

Bug Fixes:

• Parameter Validation:
  • Added a check in eval_many method to raise a ValueError when no expressions are provided.

Code Imports:

• Additional Imports:
  • Added Number from numbers to sharrow/relationships.py.
  • Imported CachedTree in sharrow/relationships.py.

These changes collectively improve the efficiency and robustness of expression evaluation and data handling in the sharrow package.