fix(FeatherMask): correct negative zero indexing for right/bottom feathering (Comfy-Org#12881)

Author: alvinttang

comfy_extras/nodes_mask.py

@@ -330,15 +330,15 @@ def execute(cls, mask, left, top, right, bottom) -> IO.NodeOutput:
 
         for x in range(right):
             feather_rate = (x + 1) / right
-            output[:, :, -x] *= feather_rate
+            output[:, :, -(x + 1)] *= feather_rate
 
         for y in range(top):
             feather_rate = (y + 1) / top
             output[:, y, :] *= feather_rate
 
         for y in range(bottom):
             feather_rate = (y + 1) / bottom
-            output[:, -y, :] *= feather_rate
+            output[:, -(y + 1), :] *= feather_rate
 
         return IO.NodeOutput(output)