修复序列帧去背景队列与幂等发布

序列帧去背景改用本地绿幕算法并在 durable 父任务内并行处理。

将去背景操作加入生成结果白名单，并按 operation_id 隔离帧对象路径。

去背景结果发布为新的序列资源、素材和画布图层，同时保留原始序列。

同步前端生成占位、相关测试及队列与资源契约文档。

src/components/image-editor/ImageCanvasGenerationDialogModel.test.ts

@@ -14,6 +14,7 @@ import {
   closeGenerateComposerDialog,
   createAudioRedrawGenerationDialogDraft,
   createBackgroundMusicGenerationDialogDraft,
+  createCharacterAnimationBackgroundRemovalDialogDraft,
   createCharacterAnimationGenerationDialogDraft,
   createCharacterAnimationPanelDraft,
   createCharacterGenerationDialogDraft,
@@ -559,6 +560,33 @@ describe('ImageCanvasGenerationDialogModel', () => {
     });
   });
 
+  it('creates a separate character animation placement for background removal', () => {
+    expect(
+      createCharacterAnimationBackgroundRemovalDialogDraft({
+        sourceLayer: createLayer({
+          id: 'layer-animation',
+          assetKind: 'character-animation',
+        }),
+        assetLabel: '源动画 去背景',
+      }),
+    ).toMatchObject({
+      mode: 'character-animation',
+      prompt: '去除背景',
+      assetLabel: '源动画 去背景',
+      status: 'generating',
+      composerOpen: false,
+      sourceLayerId: 'layer-animation',
+      placeholder: {
+        x: 472,
+        y: 140,
+        width: 320,
+        height: 240,
+        originalWidth: 1024,
+        originalHeight: 768,
+      },
+    });
+  });
+
   it('restores remodel prompts from user-visible generation input snapshots only', () => {
     const cases: Array<{
       fields: NonNullable<CanvasLayer['generationInputs']>['fields'];

src/components/image-editor/ImageCanvasGenerationDialogModel.ts

@@ -869,9 +869,7 @@ function getNormalizedString(
 function getNormalizedStringArray(sourceLayer: CanvasLayer, id: string) {
   return (sourceLayer.generationInputs?.fields ?? [])
     .filter((field) => field.id === id)
-    .flatMap((field) =>
-      typeof field.value === 'string' ? [field.value] : [],
-    );
+    .flatMap((field) => (typeof field.value === 'string' ? [field.value] : []));
 }
 
 function getNormalizedNumber(
@@ -2196,6 +2194,33 @@ export function createQuickEditGenerationDialogDraft({
   };
 }
 
+export function createCharacterAnimationBackgroundRemovalDialogDraft({
+  sourceLayer,
+  assetLabel,
+  status = 'generating',
+}: {
+  sourceLayer: CanvasLayer;
+  assetLabel?: string;
+  status?: CanvasGenerationDialogState['status'];
+}): Omit<CanvasGenerationDialogState, 'id'> {
+  return {
+    mode: 'character-animation',
+    prompt: '去除背景',
+    assetLabel,
+    status,
+    composerOpen: false,
+    sourceLayerId: sourceLayer.id,
+    placeholder: {
+      x: sourceLayer.x + sourceLayer.width + 32,
+      y: sourceLayer.y,
+      width: sourceLayer.width,
+      height: sourceLayer.height,
+      originalWidth: sourceLayer.originalWidth || sourceLayer.width,
+      originalHeight: sourceLayer.originalHeight || sourceLayer.height,
+    },
+  };
+}
+
 export function createLegacyImageRedrawGenerationDialogDraft({
   sourceLayer,
   canvasSize,

src/components/image-editor/useImageCanvasGenerationWorkflow.ts

@@ -67,6 +67,7 @@ import {
   closeGenerateComposerDialog,
   createAudioRedrawGenerationDialogDraft,
   createBackgroundMusicGenerationDialogDraft,
+  createCharacterAnimationBackgroundRemovalDialogDraft,
   createCharacterAnimationGenerationDialogDraft,
   createCharacterGenerationDialogDraft,
   createEditDialogDraft,
@@ -3697,13 +3698,33 @@ export function useImageCanvasGenerationWorkflow({
       setMetadataLayer(null);
       setCropExpandPanel(null);
       setQuickEditPanel(null);
+      const assetLabel = `${sourceLayer.title} 去背景`;
+      const backgroundRemovalDialog = applyProjectSnapshot
+        ? createCharacterAnimationBackgroundRemovalDialogDraft({
+            sourceLayer,
+            assetLabel,
+          })
+        : null;
+      const backgroundRemovalPlacement = backgroundRemovalDialog
+        ? openPlacedCanvasGenerationDialog(backgroundRemovalDialog)
+        : undefined;
+      const backgroundRemovalDialogId = backgroundRemovalPlacement?.dialogId;
       try {
         const result = await removeEditorCharacterAnimationBackground({
           projectId,
           sourceLayerId: sourceLayer.id,
           sourceResourceId: sourceLayer.resourceId,
           assetFolderId,
-          assetLabel: `${sourceLayer.title} 去背景`,
+          assetLabel,
+          ...(backgroundRemovalPlacement?.placeholder
+            ? {
+                canvasCompletion: {
+                  dialogId: backgroundRemovalDialogId,
+                  title: assetLabel,
+                  placeholder: backgroundRemovalPlacement.placeholder,
+                },
+              }
+            : {}),
           generationInputs: buildDeterministicGenerationInputs(
             'character-animation.remove-background',
             sourceLayer,
@@ -3712,10 +3733,17 @@ export function useImageCanvasGenerationWorkflow({
         await applyQueuedEditorGenerationProject(
           result,
           projectId,
-          applyProjectSnapshot,
+          (project) =>
+            applyProjectSnapshot?.(project, {
+              type: 'remove-background',
+              count: 1,
+            }),
           refreshTaskListForQueuedGeneration,
           onWalletBalanceMayHaveChanged,
           showGenerationWarning,
+          backgroundRemovalDialogId,
+          (project) =>
+            preserveSourceLayerInProjectSnapshot(project, sourceLayer),
         );
         try {
           await Promise.resolve(refreshAssetLibrary?.());
@@ -3723,6 +3751,19 @@ export function useImageCanvasGenerationWorkflow({
           // 服务端已原子落库成功；列表刷新失败不能把成功事实伪装成去背景失败。
         }
       } catch (error) {
+        if (backgroundRemovalDialogId) {
+          updateCanvasGenerationDialogById(
+            backgroundRemovalDialogId,
+            (dialog) => ({
+              ...dialog,
+              status: 'failed',
+              errorMessage:
+                error instanceof Error && error.message.trim()
+                  ? error.message
+                  : '去除序列帧背景失败',
+            }),
+          );
+        }
         window.alert(
           error instanceof Error && error.message.trim()
             ? error.message
@@ -3747,6 +3788,7 @@ export function useImageCanvasGenerationWorkflow({
       assetFolderId,
       closeGenerationTransientState,
       onWalletBalanceMayHaveChanged,
+      openPlacedCanvasGenerationDialog,
       projectId,
       refreshAssetLibrary,
       refreshTaskListForQueuedGeneration,
@@ -3755,6 +3797,7 @@ export function useImageCanvasGenerationWorkflow({
       setMetadataLayer,
       setQuickEditPanel,
       showGenerationWarning,
+      updateCanvasGenerationDialogById,
     ],
   );