[feat] Add Vue widget serialization store for custom widgets

src/stores/vueWidgetSerializationStore.ts

@@ -0,0 +1,63 @@
+/**
+ * Store for managing Vue widget serialization functions.
+ * This allows Vue components to register serialization handlers that can be
+ * accessed by LiteGraph widgets for workflow saving/loading.
+ */
+
+type SerializationFunction = () => Promise<string>
+
+class VueWidgetSerializationStore {
+  private registry = new Map<string, SerializationFunction>()
+
+  /**
+   * Register a serialization function for a widget
+   * @param key Unique identifier for the widget (e.g., "{nodeId}-{widgetName}")
+   * @param serializeFn Function that serializes the widget value
+   */
+  register(key: string, serializeFn: SerializationFunction): void {
+    this.registry.set(key, serializeFn)
+  }
+
+  /**
+   * Unregister a serialization function
+   * @param key The key used during registration
+   */
+  unregister(key: string): void {
+    this.registry.delete(key)
+  }
+
+  /**
+   * Get a serialization function for a widget
+   * @param key The key to look up
+   * @returns The serialization function if found, undefined otherwise
+   */
+  get(key: string): SerializationFunction | undefined {
+    return this.registry.get(key)
+  }
+
+  /**
+   * Check if a serialization function is registered
+   * @param key The key to check
+   * @returns True if registered, false otherwise
+   */
+  has(key: string): boolean {
+    return this.registry.has(key)
+  }
+
+  /**
+   * Clear all registered serialization functions
+   */
+  clear(): void {
+    this.registry.clear()
+  }
+
+  /**
+   * Get all registered keys (useful for debugging)
+   */
+  getKeys(): string[] {
+    return Array.from(this.registry.keys())
+  }
+}
+
+// Create singleton instance
+export const vueWidgetSerializationStore = new VueWidgetSerializationStore()