Refactor and enhance type hints across multiple modules

- Updated the `from_tuple` method in `Prof` class to specify return type.
- Added type hints for various methods in `LehmannsClient`, `OpenAI`, `WebRequest`, and `ZoteroController` classes to improve code clarity and type safety.
- Modified `pdf_to_csv` function to return a string instead of a DataFrame.
- Enhanced error handling and type hints in `wordparser` and `xmlparser` modules.
- Removed unused UI file `Ui_medianadder.ts`.
- Improved the layout and structure of the `semesterapparat_ui` to enhance user experience.
- Updated file picker to support `.doc` files in addition to `.docx`.
- Added unique item handling in `Ui` class to prevent duplicates in apparat list.
- General code cleanup and consistency improvements across various files.

src/logic/c_sort.py

@@ -1,36 +1,4 @@
-def parse_semester(semester: str):
-    """
-    Parses the semester string into a sortable format.
-    Returns a tuple of (year, type), where type is 0 for SoSe and 1 for WiSe.
-    """
-    if semester.startswith("SoSe"):
-        return int(semester.split()[1]), 0
-    elif semester.startswith("WiSe"):
-        year_part = semester.split()[1]
-        start_year, _ = map(int, year_part.split("/"))
-        return start_year, 1
-    else:
-        raise ValueError(f"Invalid semester format: {semester}")
-
-
-def custom_sort(entries):
-    """
-    Sorts the list of tuples based on the custom schema.
-
-    :param entries: List of tuples in the format (str, int, int).
-    :return: Sorted list of tuples.
-    """
-    return sorted(
-        entries,
-        key=lambda entry: (
-            parse_semester(entry[0]),  # Sort by semester parsed as (year, type)
-            entry[1],  # Then by the second element of the tuple
-            entry[2],  # Finally by the third element of the tuple
-        ),
-    )
-
-
-def parse_semester(semester: str):
+def parse_semester(semester: str) -> tuple[int, int]:
     """
     Parses the semester string into a sortable format.
     Returns a tuple of (year, type), where type is 0 for SoSe and 1 for WiSe.
@@ -48,6 +16,23 @@ def parse_semester(semester: str):
         raise ValueError(f"Invalid semester format: {semester}")
 
 
+def custom_sort(entries) -> list:
+    """
+    Sorts the list of tuples based on the custom schema.
+
+    :param entries: List of tuples in the format (str, int, int).
+    :return: Sorted list of tuples.
+    """
+    return sorted(
+        entries,
+        key=lambda entry: (
+            parse_semester(entry[0]),  # Sort by semester parsed as (year, type)
+            entry[1],  # Then by the second element of the tuple
+            entry[2],  # Finally by the third element of the tuple
+        ),
+    )
+
+
 def sort_semesters_list(semesters: list) -> list:
     """
     Sorts a list of semester strings based on year and type.