feat: Add KoikatsuBlenderPipeline addon with import/export functionality

- Add core addon files (__init__.py, KKPanel.py, preferences.py, common.py)
- Add import pipeline with armature, mesh, and material modification modules
- Add export pipeline with material baking and FBX preparation utilities
- Add material combiner tool for texture atlas generation and optimization
- Add extras utilities for animation, rigging, and asset management
- Add bone orientation data from better_fbx for accurate skeletal structure
- Add comprehensive documentation and wiki with multi-language support (EN, JP, ZH)
- Add animation library retargeting lists for ARP and Rokoko motion capture
- Add Rigify integration scripts for advanced rigging workflows
- Add shader file (KK Shader V8.0.blend) for material rendering
- Add manifest and license files for addon distribution
- Add changelog documenting version history and improvements
- Initialize complete Blender addon project for Koikatsu character import/export

exporting/material_combiner/get_pillow.py

@@ -0,0 +1,30 @@
+import os
+import subprocess
+import sys
+from typing import Set
+from . import globs
+from ... import common as c
+from ...interface.dictionary_en import t
+import bpy
+
+class InstallPIL(bpy.types.Operator):
+    bl_idname = 'kkbp.get_pillow'
+    bl_label = 'Install Pillow'
+    bl_description = t('pillow_tt')
+
+    def execute(self, context: bpy.types.Context) -> Set[str]:
+        try:
+            from PIL import Image, ImageChops
+        except ImportError:
+            self._install_pillow()
+
+        globs.pil_exist = 'restart'
+
+        self.report({'INFO'}, 'Installation complete')
+        return {'FINISHED'}
+
+    @staticmethod
+    def _install_pillow() -> None:
+        from pip import _internal
+        _internal.main(['install', 'pip', 'setuptools', 'wheel', '-U', '--user'])
+        _internal.main(['install', 'Pillow', '--user'])