Enhance spreadsheet data handling

- Added a function to convert mixed column types.
- Updated the main reading function to use this new conversion.
- Improved error handling for reading TSV files.

src/spreadsheet.py

@@ -13,7 +13,26 @@ def read_rules_from_spreadsheet(url: str) -> DataFrame | None:
     """
     try:
         # Since the output is a TSV, we use `pd.read_csv` with `sep='\t'` to specify tab-separated values.
-        return pd.read_csv(url, sep="\t")
+        df = pd.read_csv(url, sep="\t")
+        df = convert_mixed_columns(df)
+
+        # Convert columns to appropriate types based on their content.
+        return df
+
     except Exception as e:
         print(f"Failed to read the TSV from the URL: {e}")
         return None
+
+
+def convert_mixed_columns(df):
+    """Converts columns in a DataFrame to appropriate types based on their content.
+
+    Args:
+        df (DataFrame): The DataFrame whose columns are to be converted.
+
+    Returns:
+        DataFrame: The DataFrame with columns converted to appropriate types.
+    """
+    df = df.apply(lambda c: c.astype(object) if any(str(x).replace(".", "", 1).isdigit() for x in c) else c.astype(str))
+
+    return df