feat(fx): 添加像素排序 (Pixel Sort) 滤镜

- 新增 '像素排序' 滤镜，实现类似 Photoshop Pixel Sort 效果
- 支持水平/垂直方向排序
- 支持多种排序依据：亮度、色相、红/绿/蓝通道
- 支持自动阈值计算（使用图像亮度中位数）
- 支持自定义遮罩阈值
- 支持反向排序
- 支持块大小参数
- 添加相关单元测试

konabot/plugins/fx_process/fx_handle.py

@@ -1354,6 +1354,140 @@ class ImageFilterImplement:
         images.append(text_image)
         return image
 
+    # Pixel Sort - 像素排序效果
+    @staticmethod
+    def apply_pixel_sort(
+        image: Image.Image,
+        direction: str = "horizontal",
+        threshold: float = 0.0,
+        auto_threshold: bool = True,
+        sort_by: str = "brightness",
+        mask_threshold: float = 128.0,
+        reverse: bool = False,
+        block_size: int = 1
+    ) -> Image.Image:
+        """
+        Pixel Sort 效果
+        
+        参数:
+            image: 输入图像
+            direction: 排序方向，"horizontal"(水平) 或 "vertical"(垂直)
+            threshold: 亮度阈值 (0-255)，低于此值的像素会被排序（仅在 auto_threshold=False 时生效）
+            auto_threshold: 是否自动计算阈值（使用图像中位数）
+            sort_by: 排序依据，"brightness"(亮度)、"hue"(色相)、"red"、"green"、"blue"
+            mask_threshold: 遮罩阈值 (0-255)，决定哪些像素参与排序
+            reverse: 是否反向排序
+            block_size: 块大小，每 N 行/列作为一个整体排序单位
+        """
+        if image.mode != 'RGBA':
+            image = image.convert('RGBA')
+        
+        arr = np.array(image)
+        height, width = arr.shape[:2]
+        
+        # 获取排序属性
+        def get_sort_value(pixel):
+            r, g, b = pixel[0], pixel[1], pixel[2]
+            if sort_by == "brightness":
+                return 0.299 * r + 0.587 * g + 0.114 * b
+            elif sort_by == "hue":
+                max_c = max(r, g, b)
+                min_c = min(r, g, b)
+                diff = max_c - min_c
+                if diff == 0:
+                    return 0
+                if max_c == r:
+                    return 60 * (((g - b) / diff) % 6)
+                elif max_c == g:
+                    return 60 * ((b - r) / diff + 2)
+                else:
+                    return 60 * ((r - g) / diff + 4)
+            elif sort_by == "red":
+                return r
+            elif sort_by == "green":
+                return g
+            elif sort_by == "blue":
+                return b
+            return 0.299 * r + 0.587 * g + 0.114 * b
+        
+        # 自动计算阈值
+        if auto_threshold:
+            # 使用图像亮度中位数作为阈值
+            gray = np.array(image.convert('L'))
+            mask_threshold = float(np.median(gray))
+        
+        # 创建遮罩：哪些像素需要排序
+        mask = np.zeros((height, width), dtype=bool)
+        for y in range(height):
+            for x in range(width):
+                brightness = 0.299 * arr[y, x, 0] + 0.587 * arr[y, x, 1] + 0.114 * arr[y, x, 2]
+                mask[y, x] = brightness >= mask_threshold
+        
+        result = arr.copy()
+        
+        if direction.lower() in ["horizontal", "h", "水平"]:
+            # 水平排序（逐行）
+            for y in range(height):
+                # 收集当前行中需要排序的像素
+                if block_size > 1:
+                    # 按块处理
+                    for block_start in range(0, width, block_size):
+                        block_end = min(block_start + block_size, width)
+                        pixels = []
+                        indices = []
+                        for x in range(block_start, block_end):
+                            if mask[y, x]:
+                                pixels.append(arr[y, x].copy())
+                                indices.append(x)
+                        if len(pixels) > 1:
+                            # 按指定属性排序
+                            sorted_pixels = sorted(pixels, key=get_sort_value, reverse=reverse)
+                            for i, x in enumerate(indices):
+                                result[y, x] = sorted_pixels[i]
+                else:
+                    # 逐像素处理
+                    pixels = []
+                    indices = []
+                    for x in range(width):
+                        if mask[y, x]:
+                            pixels.append(arr[y, x].copy())
+                            indices.append(x)
+                    if len(pixels) > 1:
+                        sorted_pixels = sorted(pixels, key=get_sort_value, reverse=reverse)
+                        for i, x in enumerate(indices):
+                            result[y, x] = sorted_pixels[i]
+        
+        elif direction.lower() in ["vertical", "v", "垂直"]:
+            # 垂直排序（逐列）
+            for x in range(width):
+                if block_size > 1:
+                    # 按块处理
+                    for block_start in range(0, height, block_size):
+                        block_end = min(block_start + block_size, height)
+                        pixels = []
+                        indices = []
+                        for y in range(block_start, block_end):
+                            if mask[y, x]:
+                                pixels.append(arr[y, x].copy())
+                                indices.append(y)
+                        if len(pixels) > 1:
+                            sorted_pixels = sorted(pixels, key=get_sort_value, reverse=reverse)
+                            for i, y in enumerate(indices):
+                                result[y, x] = sorted_pixels[i]
+                else:
+                    pixels = []
+                    indices = []
+                    for y in range(height):
+                        if mask[y, x]:
+                            pixels.append(arr[y, x].copy())
+                            indices.append(y)
+                    if len(pixels) > 1:
+                        sorted_pixels = sorted(pixels, key=get_sort_value, reverse=reverse)
+                        for i, y in enumerate(indices):
+                            result[y, x] = sorted_pixels[i]
+        
+        return Image.fromarray(result, 'RGBA')
+
 
     
 class ImageFilterEmpty: