feat(canvas): 画布工作台 - 新增生成副本并修复大型画布性能、素材同步与删除校验

统一图片与视频副本的生成落点并保留参考连接。\n优化大型画布节点虚拟化、媒体懒加载、拖拽与详情进入路径。\n修复素材主版本 ID 同步及删除时的画布独立引用校验。

web/src/components/canvas/canvas-context-menu.tsx

@@ -38,6 +38,7 @@ type CanvasNodeContextMenuProps = {
     onRedo: () => void;
     onPaste: () => void;
     onCopyNode: () => void;
+    onCreateGenerationCopy: () => void;
     onDuplicate: () => void;
     onDelete: () => void;
     onSaveAsset: () => void;
@@ -72,6 +73,7 @@ export function CanvasNodeContextMenu({
     onRedo,
     onPaste,
     onCopyNode,
+    onCreateGenerationCopy,
     onDuplicate,
     onDelete,
     onSaveAsset,
@@ -201,6 +203,7 @@ export function CanvasNodeContextMenu({
                                     <MenuButton icon={<Copy />} label="复制节点" shortcut="⌘C" onClick={() => runAction(onCopyNode)} />
                                     {isImage ? <MenuButton icon={<Clipboard />} label="复制图片" disabled={!hasNodeContent} onClick={() => runAction(onCopyContent)} /> : null}
                                     <MenuButton icon={<Link2 />} label={isImage ? "复制图片地址" : "复制视频地址"} disabled={!canCopyMediaUrl} onClick={() => runAction(onCopyMediaUrl)} />
+                                    <MenuButton icon={<Copy />} label="创建生成副本" onClick={() => runAction(onCreateGenerationCopy)} />
                                     <MenuButton icon={<Layers3 />} label="创建参数变体" shortcut="⌘D" onClick={() => runAction(onDuplicate)} />
                                     <MenuButton icon={<Trash2 />} label="删除节点" danger onClick={() => runAction(onDelete)} />
                                 </>