Sync backend/frontend versions to Docker/VERSION and read version from it

backend/tests/test_version.py

@@ -0,0 +1,15 @@
+from __future__ import annotations
+
+from pathlib import Path
+
+import app
+
+
+def test_app_version_matches_docker_version() -> None:
+    """The backend version should match the signed off Docker release version."""
+
+    repo_root = Path(__file__).resolve().parents[2]
+    version_file = repo_root / "Docker" / "VERSION"
+    expected = version_file.read_text(encoding="utf-8").strip().lstrip("v")
+
+    assert app.__version__ == expected