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

interface/dictionary_en.py

@@ -112,6 +112,11 @@ translation_dictionary = {
 
     'rigify_convert'            : "Convert for Rigify",
     'rigify_convert_tt'         : "Runs several scripts to convert a KKBP armature to be Rigify compatible",
+    'better_fbx_bones'          : "Apply Better FBX Bone Orientations",
+    'better_fbx_bones_tt'       : "Modifies bone orientations to be more natural. This makes bones extend along limbs instead of pointing upward",
+    'delete_accessory_bones'    : "Delete Accessory Bones",
+    'delete_accessory_bones_tt' : "When enabled, applying bone orientations will also delete hair, clothing and other accessory bones, keeping only core body bones",
+
     'sep_eye'                   : "Separate Eyes and Eyebrows",
     'sep_eye_tt'                : "Separates the Eyes and Eyebrows from the Body object and links the shapekeys to the Body object. Useful for when you want to make eyes or eyebrows appear through the hair using the Cryptomatte features in the compositor",
     'bone_visibility'           : "Show bones for current outfit",

interface/dictionary_jp.py

@@ -108,6 +108,11 @@ translation_dictionary = {
 
     'rigify_convert'            : "Rigifyアーマチュアに変えて",
     'rigify_convert_tt'         : "このボタンをクリックしたら、KKBPアーマチュアをRigifyアーマチュアに変えて",
+    'better_fbx_bones'          : "Better FBXボーン方向を適用",
+    'better_fbx_bones_tt'       : "ボーンの方向をより自然な方向に変更します。ボーンが上向きではなく、肢体に沿って伸びるようになります",
+    'delete_accessory_bones'    : "アクセサリボーンを削除",
+    'delete_accessory_bones_tt' : "有効にすると、ボーン方向を適用する際に髪や服などのアクセサリボーンを削除し、コアボディボーンのみを保持します",
+
     'sep_eye'                   : "EyesやEyebrowsやBodyのオブジェクトから別々になって",
     'sep_eye_tt'                : "BodyのオブジェクトからEyesやEyebrowsマテリアルを別のオブジェクトを別々にして、シェイプ キーをBodyオブジェクトにリンクされる",
     'bone_visibility'           : "現在の服のボーンを表示して",

interface/dictionary_zh.py

@@ -112,6 +112,11 @@ translation_dictionary = {
 
     'rigify_convert'            : "转换为Rigify",
     'rigify_convert_tt'         : "运行几个脚本，将KKBP骨架转换为兼容Rigify的骨架",
+    'better_fbx_bones'          : "应用Better FBX骨骼方向",
+    'better_fbx_bones_tt'       : "将骨骼方向修改为更自然的方向。这会让骨骼沿着肢体方向延伸，而不是都朝上",
+    'delete_accessory_bones'    : "删除配饰骨骼",
+    'delete_accessory_bones_tt' : "勾选后，应用骨骼方向时会删除头发、衣服等配饰骨骼，只保留核心人体骨骼",
+
     'sep_eye'                   : "分离眼睛和眉毛",
     'sep_eye_tt'                : "将眼睛和眉毛从身体对象中分离出来，并将形态键链接到身体对象。当您想让眼睛或眉毛通过头发透视时，该功能非常有用",
     'bone_visibility'           : "更新骨骼可见性",