Revert "webui: organize config page with subtabs"

This reverts commit 2f973a279c.

tests/test_http_api_contract.py

@@ -352,6 +352,7 @@ def test_embedded_webui_config_page_is_grouped():
     assert "Relay Outputs" in source
     assert "Temperature Assignment" in source
     assert "Maintenance" in source
+<<<<<<< HEAD
 
 
 def test_embedded_webui_config_subtabs():
@@ -375,3 +376,5 @@ def test_embedded_webui_api_badge_labels_are_clear():
     assert "API Live" in source
     assert "API Error" in source
     assert 'textContent="Offline"' not in source
+=======
+>>>>>>> parent of 2f973a2 (webui: organize config page with subtabs)