Python dynamic imports via importlib and __import__() not indexed as symbol references

[Widthdom]

Summary

Python code using importlib.import_module('module.name'), __import__('package'), or importlib.util.find_spec() never creates import symbols or references. These dynamic import patterns are idiomatic in plugin systems, configuration-driven module loading, and lazy imports. Currently only static import and from ... import statements are recognized; all programmatic import sites are invisible to the call graph and symbol dependency map.

Where

• src/CodeIndex/Indexer/Symbols/SymbolExtractor.Python.cs:56-126 — TryExpandPythonImportSymbols only processes static import statements (regex on lines 12-13)
• src/CodeIndex/Indexer/References/Languages/PythonReferenceExtractor.cs:118-150 — EmitDecoratorReferences does not cover dynamic module resolution patterns

Suggested approach

1. Add regex patterns for importlib.import_module(...), __import__(...), and importlib.util.find_spec(...)
2. Extract the module name argument as an import symbol (with dynamic fallback kind if string is not a literal)
3. Register calls to importlib functions as references to the importlib module

[Widthdom]

Work started on branch codex/fix-issue2056.