feat: Add inpainting (局部重绘) feature for timeline editor

- Add canvas-based mask drawing tools (brush, eraser, rect, lasso)
- Add undo/redo history support for mask editing
- Integrate inpainting UI into preview player
- Add backend API endpoint for inpainting requests
- Add MediaService.inpaint method with ComfyUI workflow support
- Add Flux inpainting workflows for selfhost and RunningHub

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

api/routers/editor.py

@@ -36,6 +36,8 @@ from api.schemas.editor import (
     RegenerateImageResponse,
     RegenerateAudioRequest,
     RegenerateAudioResponse,
+    InpaintRequest,
+    InpaintResponse,
 )
 
 router = APIRouter(prefix="/editor", tags=["Editor"])
@@ -577,3 +579,107 @@ async def regenerate_frame_audio(
     except Exception as e:
         logger.error(f"Audio regeneration failed: {e}")
         raise HTTPException(status_code=500, detail=str(e))
+
+
+@router.post(
+    "/storyboard/{storyboard_id}/frames/{frame_id}/inpaint",
+    response_model=InpaintResponse
+)
+async def inpaint_frame_image(
+    storyboard_id: str = Path(..., description="Storyboard/task ID"),
+    frame_id: str = Path(..., description="Frame ID"),
+    request: InpaintRequest = None
+):
+    """
+    Inpaint (局部重绘) frame image
+
+    Uses mask to selectively regenerate parts of the image.
+    """
+    if storyboard_id not in _storyboard_cache:
+        raise HTTPException(status_code=404, detail=f"Storyboard {storyboard_id} not found")
+
+    storyboard = _storyboard_cache[storyboard_id]
+    frames = storyboard["frames"]
+
+    # Find frame
+    target_frame = None
+    frame_index = 0
+    for i, frame in enumerate(frames):
+        if frame["id"] == frame_id:
+            target_frame = frame
+            frame_index = i
+            break
+
+    if not target_frame:
+        raise HTTPException(status_code=404, detail=f"Frame {frame_id} not found")
+
+    # Get original image path
+    original_image = target_frame.get("image_path")
+    if not original_image:
+        raise HTTPException(status_code=400, detail="No image to inpaint")
+
+    if not request or not request.mask:
+        raise HTTPException(status_code=400, detail="Mask is required")
+
+    try:
+        from api.dependencies import get_pixelle_video
+        import base64
+        import tempfile
+        import os
+
+        pixelle_video = await get_pixelle_video()
+
+        # Save mask to temp file
+        mask_data = base64.b64decode(request.mask)
+        output_dir = f"output/{storyboard_id}"
+        os.makedirs(output_dir, exist_ok=True)
+        mask_path = f"{output_dir}/mask_{frame_index}.png"
+        with open(mask_path, 'wb') as f:
+            f.write(mask_data)
+
+        # Get prompt
+        prompt = request.prompt or target_frame.get("image_prompt", "")
+
+        # Call inpaint service
+        # Convert URL back to file path (URL format: http://localhost:8000/api/files/{relative_path})
+        image_file_path = original_image
+        if "/api/files/" in original_image:
+            image_file_path = "output/" + original_image.split("/api/files/")[-1]
+
+        result = await pixelle_video.media.inpaint(
+            image_path=image_file_path,
+            mask_path=mask_path,
+            prompt=prompt,
+            denoise_strength=request.denoise_strength,
+        )
+
+        if result and result.url:
+            # Save inpainted image
+            import aiohttp
+            image_path = f"{output_dir}/frame_{frame_index}_inpainted.png"
+
+            async with aiohttp.ClientSession() as session:
+                async with session.get(result.url) as resp:
+                    if resp.status == 200:
+                        with open(image_path, 'wb') as f:
+                            f.write(await resp.read())
+
+            # Update frame
+            target_frame["image_path"] = _path_to_url(image_path)
+            _storyboard_cache[storyboard_id] = storyboard
+
+            logger.info(f"Inpainted image for frame {frame_id}")
+
+            return InpaintResponse(
+                image_path=target_frame["image_path"],
+                success=True
+            )
+        else:
+            raise HTTPException(status_code=500, detail="Inpainting failed")
+
+    except ImportError as e:
+        logger.error(f"Failed to import dependencies: {e}")
+        raise HTTPException(status_code=500, detail="Inpainting service not available")
+    except Exception as e:
+        logger.error(f"Inpainting failed: {e}")
+        raise HTTPException(status_code=500, detail=str(e))

api/schemas/editor.py

@@ -108,3 +108,16 @@ class RegenerateAudioResponse(BaseModel):
     duration: float
     success: bool = True
 
+
+class InpaintRequest(BaseModel):
+    """Request to inpaint (局部重绘) frame image"""
+    mask: str = Field(..., description="Base64 encoded mask image (white=inpaint, black=keep)")
+    prompt: Optional[str] = Field(None, description="Optional prompt for inpainted region")
+    denoise_strength: float = Field(0.8, ge=0.0, le=1.0, description="Denoise strength (0.0-1.0)")
+
+
+class InpaintResponse(BaseModel):
+    """Response after inpainting"""
+    image_path: str
+    success: bool = True
+