test: define hardened Compose contract

tests/run.py

@@ -0,0 +1,20 @@
+"""Compile the contract tests, then execute unittest discovery."""
+
+from pathlib import Path
+import py_compile
+import sys
+import unittest
+
+
+TEST_DIR = Path(__file__).resolve().parent
+
+
+def main() -> int:
+    for test_file in sorted(TEST_DIR.glob("test_*.py")):
+        py_compile.compile(str(test_file), doraise=True)
+    suite = unittest.defaultTestLoader.discover(str(TEST_DIR), pattern="test_*.py")
+    return 0 if unittest.TextTestRunner(verbosity=2).run(suite).wasSuccessful() else 1
+
+
+if __name__ == "__main__":
+    sys.exit(main())