feat(importing): Add better FBX bone orientations operator and accessory bone deletion

- Add new `apply_better_fbx_orientations` operator as standalone UI action for applying bone orientations
- Add "Delete Accessory Bones" property and UI toggle in EXTRAS panel for optional bone cleanup
- Move bone orientation logic from `modify_armature` execute method to new dedicated operator
- Refactor accessory bone deletion into separate method callable from new operator
- Update panel UI to show better FBX bones operator with delete accessory bones toggle option
- Register new operator in `__init__.py` and export from modifyarmature module
- Update interface dictionaries (English, Japanese, Chinese) with new UI strings
- Enable better FBX orientations and accessory deletion only for Koikatsu armature (C) selection
- Add detailed logging for bone operation counts and status tracking

KKPanel.py

@@ -170,6 +170,11 @@ class PlaceholderProperties(PropertyGroup):
         description=t('animation_type_tt'),
         default = False)
 
+    delete_accessory_bones : BoolProperty(
+        name="Delete Accessory Bones",
+        description=t('delete_accessory_bones_tt'),
+        default = False)
+
     image_dropdown : EnumProperty(
         items=(
             ("A", t('dark_C'), "Use Day LUT to saturate image"),
@@ -378,6 +383,20 @@ class EXTRAS_PT_panel(bpy.types.Panel):
         split.label(text=t('rigify_convert'))
         split.operator('kkbp.rigifyconvert', text = '', icon='MOD_ARMATURE')
 
+        col = box.column(align=True)
+        row = col.row(align=True)
+        split = row.split(align=True, factor=splitfac)
+        split.label(text=t('better_fbx_bones'))
+        split.operator('kkbp.applybetterfbxorientations', text = '', icon='BONE_DATA')
+        row.enabled = scene.plugin_state in ['imported'] and scene.armature_dropdown == 'C'
+        row = col.row(align=True)
+        split = row.split(align=True, factor=splitfac)
+        split.label(text="")
+        split.prop(context.scene.kkbp, "delete_accessory_bones", toggle=True, text = t('delete_accessory_bones'))
+        row.enabled = scene.plugin_state in ['imported'] and scene.armature_dropdown == 'C'
+
+
+
         col = box.column(align=True)
         row = col.row(align=True)
         split = row.split(align=True, factor=splitfac)