Port to libcst

[charles-turner-1]

Replace AST with libcst, should let us do some smarter syntax tree traversal in order to catch chained calls, etc properly

[codecov]

Codecov Report

❌ Patch coverage is 97.77778% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 96.62%. Comparing base (1cb3750) to head (21d7c58).
⚠️ Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
src/access_py_telemetry/ast.py	97.77%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #64      +/-   ##
==========================================
+ Coverage   95.15%   96.62%   +1.46%     
==========================================
  Files           7        7              
  Lines         475      504      +29     
==========================================
+ Hits          452      487      +35     
+ Misses         23       17       -6     

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[Copilot]

Pull Request Overview

This PR replaces the standard AST (Abstract Syntax Tree) with libcst (Concrete Syntax Tree) to enable more sophisticated syntax tree traversal and better handling of chained method calls. The change allows for catching complex patterns like method chaining that were previously difficult or impossible to analyze.

Key changes:

• Migration from Python's built-in ast module to libcst for all syntax tree operations
• Introduction of a ChainSimplifier transformer to handle method chaining scenarios
• Enhanced argument extraction with better support for various data types and user namespace resolution

Reviewed Changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 5 comments.

File	Description
tests/test_ast.py	Updated all test cases to use libcst, added comprehensive tests for chain simplification and chained function calls
src/access_py_telemetry/ast.py	Complete rewrite using libcst with new ChainSimplifier class and enhanced CallListener visitor
pyproject.toml	Added libcst dependency and updated mypy configuration
.pre-commit-config.yaml	Updated mypy arguments to accommodate new code patterns

Comments suppressed due to low confidence (1)

tests/test_ast.py:399

• The expected value has changed from ["some_item"] to ["'some_item'"] (with quotes), but there's no explanation for this behavior change. This suggests the string handling in argument extraction may have changed semantics, which should be documented or tested explicitly.

            ("mock", "MyClass.__getitem__", ["'some_item'"], {}),

[Copilot]

The mypy disable comment uses 'has-type' but this should be 'type-arg' or another valid mypy error code. 'has-type' is not a recognized mypy error code.

Suggested change

# mypy: disable-error-code=has-type