Python: add new shared-CFG-backed control flow graph (additive)

python/ql/consistency-queries/CfgConsistency.ql

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+import semmle.python.controlflow.internal.AstNodeImpl
+import ControlFlow::Consistency

python/ql/lib/change-notes/2026-05-19-add-shared-cfg.md

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+---
+category: minorAnalysis
+---
+* A new Python control flow graph implementation has been added under `semmle.python.controlflow.internal.Cfg` (backed by `AstNodeImpl.qll`), built on the shared `codeql.controlflow.ControlFlowGraph` library. It is not yet used by the dataflow library or any production query; the legacy CFG in `semmle/python/Flow.qll` remains the default. The new library is exposed for tests and for upcoming migrations.

python/ql/lib/change-notes/2026-06-04-cfg-parameter-annotations.md

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+---
+category: minorAnalysis
+---
+* The new (shared-CFG-based) Python control flow graph now visits parameter and return type annotations as CFG nodes for function definitions, matching the legacy CFG. This restores annotation-based type tracking through framework models such as FastAPI's `Depends()`, Pydantic request models, Starlette `WebSocket` handlers, and any other models that flow a class reference through `Parameter.getAnnotation()` to identify instances of the annotated class.

python/ql/lib/ide-contextual-queries/printCfg.ql

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+/**
+ * @name Print CFG
+ * @description Produces a representation of a file's Control Flow Graph.
+ *              This query is used by the VS Code extension.
+ * @id py/print-cfg
+ * @kind graph
+ * @tags ide-contextual-queries/print-cfg
+ */
+
+import semmle.python.Files as Files
+// import semmle.python.Scope
+import semmle.python.controlflow.internal.AstNodeImpl
+
+external string selectedSourceFile();
+
+private predicate selectedSourceFileAlias = selectedSourceFile/0;
+
+external int selectedSourceLine();
+
+private predicate selectedSourceLineAlias = selectedSourceLine/0;
+
+external int selectedSourceColumn();
+
+private predicate selectedSourceColumnAlias = selectedSourceColumn/0;
+
+module ViewCfgQueryInput implements ControlFlow::ViewCfgQueryInputSig<Files::File> {
+  predicate selectedSourceFile = selectedSourceFileAlias/0;
+
+  predicate selectedSourceLine = selectedSourceLineAlias/0;
+
+  predicate selectedSourceColumn = selectedSourceColumnAlias/0;
+
+  predicate cfgScopeSpan(
+    Ast::Callable scope, Files::File file, int startLine, int startColumn, int endLine,
+    int endColumn
+  ) {
+    file = scope.getLocation().getFile() and
+    scope.getLocation().hasLocationInfo(_, startLine, startColumn, endLine, endColumn)
+  }
+}
+
+import ControlFlow::ViewCfgQuery<Files::File, ViewCfgQueryInput>