Collapse duplicate repository graph nodes

tests/test_graph_explorer.py

@@ -72,6 +72,57 @@ def test_graph_explorer_manifest_and_payload_validate() -> None:
     assert "removed nodes are removed" in payload["filter"]["connected_edge_behavior"]
 
 
+def test_graph_explorer_collapses_discovered_repository_nodes() -> None:
+    graph = {
+        "apiVersion": "railiance.fabric/v1alpha1",
+        "kind": "FabricGraphExport",
+        "generated_at": "2026-05-21T00:00:00Z",
+        "source": {"repo": "fixture-repo", "commit": "abc123"},
+        "nodes": [
+            {
+                "id": "discovery:fixture-repo:repository:fixture-repo",
+                "kind": "Repository",
+                "name": "Fixture Repo",
+                "repo": "fixture-repo",
+                "domain": "testing",
+                "lifecycle": "active",
+                "attributes": {"discovery_origin": "deterministic"},
+            },
+            {
+                "id": "discovery:fixture-repo:library:fixture-service",
+                "kind": "Library",
+                "name": "fixture-service",
+                "repo": "fixture-repo",
+                "domain": "testing",
+                "lifecycle": "active",
+                "attributes": {"language": "python"},
+            },
+        ],
+        "edges": [
+            {
+                "from": "discovery:fixture-repo:repository:fixture-repo",
+                "to": "discovery:fixture-repo:library:fixture-service",
+                "type": "declares_package",
+            }
+        ],
+    }
+
+    payload = fabric_graph_explorer_payload(
+        graph,
+        [{"slug": "fixture-repo", "name": "Fixture Repo"}],
+        {"fixture-repo"},
+    )
+
+    nodes = [element for element in payload["elements"] if "source" not in element["data"]]
+    edges = [element for element in payload["elements"] if "source" in element["data"]]
+    repository_nodes = [node for node in nodes if node["data"]["kind"] == "Repository"]
+    declares_package = next(edge for edge in edges if edge["data"]["edgeType"] == "declares_package")
+
+    assert [node["data"]["id"] for node in repository_nodes] == ["repo:fixture-repo"]
+    assert declares_package["data"]["source"] == "repo:fixture-repo"
+    assert declares_package["data"]["target"] == "discovery:fixture-repo:library:fixture-service"
+
+
 def test_cli_exports_graph_explorer_payload(capsys) -> None:
     assert cli_main(["export", "--format", "graph-explorer"]) == 0
     payload = json.loads(capsys.readouterr().out)