Panels dialog saves a ready I/O port draft on close and keeps an unfinished one; one qualified message-name rule on both sides

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

backend/tests/flow/test_messages.py

@@ -2,7 +2,13 @@ import json
 
 import pytest
 
-from fluksio.flow.messages import DType, MessageSpec, flow_of, qualify
+from fluksio.flow.messages import (
+    DType,
+    MessageSpec,
+    flow_of,
+    qualify,
+    validate_qualified,
+)
 
 
 def test_port_defaults_to_last_name_segment():
@@ -201,3 +207,14 @@ def test_a_value_that_refers_to_itself_does_not_hang_the_check():
     loop: dict = {}
     loop["self"] = loop
     spec.check(loop)
+
+
+@pytest.mark.parametrize("name", ["home.doorbell", "house.kitchen.temperature"])
+def test_a_qualified_name_names_its_flow(name):
+    assert validate_qualified(name) == name
+
+
+@pytest.mark.parametrize("name", ["doorbell", "Home.x", "home.", "home.a-b", "home..x"])
+def test_anything_else_is_refused_with_the_rule(name):
+    with pytest.raises(ValueError, match="flow.name"):
+        validate_qualified(name)