feat: 用缓存处理对话中的项目切换问题

src/components/Canvas/FlowCanvas/manager/StateManager.ts

@@ -276,7 +276,7 @@ export class StateManager {
 	}
 	/** 撤回状态 */
 	undoState() {
-		var index = this.historyIndex.value - 1
+		const index = this.historyIndex.value - 1
 		const state = this.historyList.value[index]
 		if (!state) return
 		this.historyIndex.value = index
@@ -285,7 +285,7 @@ export class StateManager {
 	}
 	/** 重做状态 */
 	redoState() {
-		var index = this.historyIndex.value + 1
+		const index = this.historyIndex.value + 1
 		const state = this.historyList.value[index]
 		if (!state) return
 		this.historyIndex.value = index