chore: import upstream snapshot with attribution

tests/fixtures/sample_calls.py

@@ -0,0 +1,26 @@
+"""Fixture: functions and methods that call each other - for call-graph extraction tests."""
+
+
+def compute_score(data):
+    return sum(data)
+
+
+def normalize(value):
+    return value / 100.0
+
+
+def run_analysis(data):
+    score = compute_score(data)
+    return normalize(score)
+
+
+class Analyzer:
+    def process(self, data):
+        return run_analysis(data)
+
+    def score(self, data):
+        return compute_score(data)
+
+    def full_pipeline(self, data):
+        raw = self.score(data)
+        return normalize(raw)