refactor: enhance docstring for identify_file method with argument details and return type

src/file_processing_tool.py

@@ -35,8 +35,14 @@ class FileIdentifier:
     def identify_file(self: Self, filepath: str):
         """
         Identifies the file type and suggests a processing action.
-        Returns a dictionary with 'filepath', 'determined_type', 'mime_type', 
-        'suggested_action', or an 'error'.
+
+        Args:
+            self (Self): The instance of the FileIdentifier class.
+            filepath (str): The path to the file to be identified.
+
+        Returns:
+            dict: A dictionary with 'filepath', 'determined_type', 'mime_type', 
+                  'suggested_action', or an 'error'.
         """
         if not os.path.exists(filepath):
             return {