Header of process and node ports follow each other both ways: a panel edit rewrites only the def line of edited code, a code save reads the header back into input ports and settings (draft and response); Space types in the node editor again

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01WgBfkm4rCmtd1T4vHWjEPx

backend/tests/api/routes/test_flows.py

@@ -557,6 +557,33 @@ async def test_the_live_socket_ends_when_its_client_goes(
     assert parked == []
 
 
+def test_saving_a_header_moves_the_node_ports_in_the_draft(
+    client: TestClient, superuser_token_headers: dict[str, str]
+) -> None:
+    saved = client.put(
+        f"{PREFIX}/header", headers=superuser_token_headers, json=a_flow("header")
+    ).json()
+
+    response = client.put(
+        f"{PREFIX}/header/nodes/logger/source",
+        headers=superuser_token_headers,
+        json={"code": "def process(reading, level, gain=2):\n    return {}\n"},
+    ).json()
+
+    assert [spec["port"] for spec in response["node"]["requires"]] == [
+        "reading",
+        "level",
+    ]
+    assert response["node"]["params"] == {"gain": 2}
+    draft = client.get(f"{PREFIX}/header", headers=superuser_token_headers).json()
+    assert draft["definition"]["version"] == response["version"]
+    assert response["version"] == saved["definition"]["version"] + 1
+    logger = next(n for n in draft["definition"]["nodes"] if n["id"] == "logger")
+    assert logger["params"] == {"gain": 2}
+
+    client.delete(f"{PREFIX}/header", headers=superuser_token_headers)
+
+
 def test_a_shared_node_in_use_is_retired_only_with_detach(
     client: TestClient, superuser_token_headers: dict[str, str]
 ) -> None: