added versioning, requirements and setup

setup.py

@@ -0,0 +1,41 @@
+#!/usr/bin/env python3
+import sys
+from setuptools import setup
+
+# Application metadata
+APP_NAME = "PNG Metadata Editor"
+APP_VERSION = "1.0.0"
+AUTHOR = "Robert Tusa"
+DESCRIPTION = "A graphical tool for viewing and editing metadata in PNG files"
+
+# Read the long description from README
+with open('README.md', 'r', encoding='utf-8') as f:
+    long_description = f.read()
+
+setup(
+    name=APP_NAME,
+    version=APP_VERSION,
+    description=DESCRIPTION,
+    long_description=long_description,
+    long_description_content_type='text/markdown',
+    author=AUTHOR,
+    author_email='robert@tusa.at',  # Replace with your email
+    url='https://git.tusa.at/robert/png-meta-editor',  # Replace with your repo
+    license='MIT',
+    python_requires='>=3.6',
+    app=['png-meta-editor.py'],  # Your main script
+    data_files=[('',
+                 ['AppIcon.icns', 'version.txt'])],  # Include these files
+    options={
+        'py2app': {
+            'argv_emulation': True,
+            'iconfile': 'AppIcon.icns',
+            'plist': {
+                'CFBundleName': APP_NAME,
+                'CFBundleShortVersionString': APP_VERSION,
+                'CFBundleVersion': APP_VERSION,
+            },
+        },
+    },
+    setup_requires=['py2app'],
+)