fix(frontend): Disabled delete node + correctly update debug menu when nodes are deleted (#3387)

* fix(frontend): Disabled delete node + correctly handle debug menu

* fix(frontend): improve reactivity

frontend/src/lib/components/apps/components/layout/AppDecisionTree.svelte

@@ -151,6 +151,21 @@
 			subGridIndex: nodes.findIndex((node) => node.id === currentNodeId)
 		}
 	}
+
+	function updateDebuggingComponents() {
+		const nodeIds = nodes.map((node) => node.id).sort()
+		const debuggingComponentsIds = Object.keys($debuggingComponents).sort()
+
+		if (JSON.stringify(nodeIds) !== JSON.stringify(debuggingComponentsIds)) {
+			debuggingComponentsIds.forEach((id) => {
+				if (!nodeIds.includes(id)) {
+					delete $debuggingComponents[id]
+				}
+			})
+		}
+	}
+
+	$: nodes && $debuggingComponents && updateDebuggingComponents()
 </script>
 
 {#if Object.keys(resolvedConditions).length === nodes.length}

frontend/src/lib/components/apps/editor/settingsPanel/DecisionTreeGraphEditor.svelte

@@ -64,7 +64,7 @@
 										nodes = removeNode(nodes, selectedNode)
 										renderCount++
 									}}
-									disabled={selectedNode?.next?.length > 1}
+									disabled={selectedNode?.next?.length > 1 || nodes.length == 1}
 								>
 									Delete node
 								</Button>