refactor(backend): clean up package re-exports, settings model properties, and unused signals

src/pygui/backend/data/csv_file_metadata.py

@@ -19,8 +19,8 @@ class CSVFileMetadata:
         """Return the first character of the wafer string, or empty if none"""
         return self.wafer[0] if self.wafer else ""
 
-    def get_date(self) -> datetime:
-        """Parsifes the date string. Returns current time if parsing fails"""
+    def get_date(self) -> datetime | None:
+        """Parsifes the date string. Returns None if parsing fails"""
         date_format = "%Y-%m-%d %H:%M:%S"
         try:
             return datetime.strptime(self.date, date_format)