Refactor dataflow operators around runtime registry

tests/test_operators.py

@@ -276,9 +276,58 @@ class DataflowOperatorTests(unittest.TestCase):
         self.assertEqual(set(NODE_TYPES), set(coverage))
         for node_type, facets in coverage.items():
             self.assertIn("config_validator", facets, node_type)
+            self.assertIn("schema_propagator", facets, node_type)
             self.assertIn("executor", facets, node_type)
             self.assertIn("sql_renderer", facets, node_type)
 
+    def test_maximum_size_linear_graph_validates_and_executes(self) -> None:
+        nodes = [
+            node(
+                "source",
+                "source.inline",
+                {
+                    "source_name": "bounded_input",
+                    "rows": [{"value": 1}],
+                },
+                x=0,
+            )
+        ]
+        edges: list[GraphEdge] = []
+        previous_id = "source"
+        for index in range(1, 99):
+            node_id = f"limit-{index}"
+            nodes.append(
+                node(
+                    node_id,
+                    "limit",
+                    {"count": 1},
+                    x=index * 10,
+                )
+            )
+            edges.append(
+                GraphEdge(
+                    id=f"edge-{index}",
+                    source=previous_id,
+                    target=node_id,
+                )
+            )
+            previous_id = node_id
+        nodes.append(node("output", "output", {}, x=990))
+        edges.append(
+            GraphEdge(
+                id="edge-99",
+                source=previous_id,
+                target="output",
+            )
+        )
+        graph = PipelineGraph(nodes=nodes, edges=edges)
+
+        self.assertEqual([], validate_graph(graph))
+        result = execute_preview(graph, row_limit=1)
+
+        self.assertEqual([{"value": 1}], result.rows)
+        self.assertEqual(100, len(result.node_diagnostics))
+
     def test_expression_node_renders_through_registered_sql_compiler(self) -> None:
         graph = PipelineGraph(
             nodes=[