sync update from LAN repo (source dhk-1 @ 3b1ec5b4)

offline-backend-20260512/backend/tests/test_migration_graph.py

@@ -14,7 +14,29 @@ def test_migration_graph_has_unique_revisions_and_one_head() -> None:
 
     revisions = list(scripts.walk_revisions())
     assert len({revision.revision for revision in revisions}) == len(revisions)
-    assert scripts.get_heads() == ["20261015_01"]
+    assert scripts.get_heads() == ["20261102_02"]
+    assert scripts.get_revision("20261026_02").down_revision == ("20261026_01", "20261022_01")
+    assert scripts.get_revision("20261026_01").down_revision == "20261025_03"
+    assert scripts.get_revision("20261023_03").down_revision == "20261023_02"
+    assert scripts.get_revision("20261023_02").down_revision == (
+        "20261024_02",
+        "20261022_02",
+    )
+    assert scripts.get_revision("20261024_02").down_revision == "20261024_01"
+    assert scripts.get_revision("20261022_02").down_revision == "20261024_01"
+    assert scripts.get_revision("20261024_01").down_revision == "20261023_01"
+    assert scripts.get_revision("20261023_01").down_revision == "20261022_03"
+    assert scripts.get_revision("20261022_03").down_revision == "20261021_01"
+    assert scripts.get_revision("20261022_01").down_revision == "20261014_02"
+    assert scripts.get_revision("20261021_01").down_revision == "20261020_01"
+    assert scripts.get_revision("20261020_01").down_revision == (
+        "20261019_01",
+        "20261014_02",
+    )
+    assert scripts.get_revision("20261019_01").down_revision == "20261015_01"
+    assert scripts.get_revision("20261014_02").down_revision == "20261014_01"
+    assert scripts.get_revision("20261014_01").down_revision == "20261009_01"
+    assert scripts.get_revision("20261009_01").down_revision == "20261006_01"
 
     assert scripts.get_revision("20260916_02").down_revision == "20260916_01"
     assert scripts.get_revision("20260916_03").down_revision == (