ModelTranslator: 终审 Minor——sidecar 用 finally 清理 + average_islands_scale 补捕 TypeError

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Tools/ModelTranslator/bl_decimate.py

@@ -166,7 +166,7 @@ def _unwrap_seam(obj, warnings, seam_angle_deg=SEAM_ANGLE_DEG):
         warnings.append("minimize_stretch 不可用（%s），跳过松弛" % e)
     try:  # 统一纹素密度，避免大岛霸占分辨率
         bpy.ops.uv.average_islands_scale()
-    except RuntimeError as e:
+    except (RuntimeError, TypeError) as e:
         warnings.append("average_islands_scale 不可用（%s），跳过纹素均衡" % e)
     try:
         bpy.ops.uv.pack_islands(rotate=True, margin=PACK_MARGIN)