Move main.py to ytsage/ and update imports

Renamed main.py to ytsage/main.py and updated relative imports to reflect the new module structure.

ytsage/main.py

@@ -0,0 +1,34 @@
+import sys
+
+from PySide6.QtWidgets import QApplication, QMessageBox
+
+from .utils.ytsage_logger import logger
+from .gui.ytsage_gui_main import YTSageApp  # Import the main application class from ytsage_gui_main
+
+
+def show_error_dialog(message):
+    error_dialog = QMessageBox()
+    error_dialog.setIcon(QMessageBox.Icon.Critical)
+    error_dialog.setText("Application Error")
+    error_dialog.setInformativeText(message)
+    error_dialog.setWindowTitle("Error")
+    error_dialog.exec()
+
+
+def main():
+    try:
+        logger.info("Starting YTSage application")
+        app = QApplication(sys.argv)
+
+        window = YTSageApp()  # Instantiate the main application class
+        window.show()
+        logger.info("Application window shown, entering main loop")
+        sys.exit(app.exec())
+    except Exception as e:
+        logger.critical(f"Critical application error: {e}", exc_info=True)
+        show_error_dialog(f"Critical error: {e}")
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    main()