Switch to using polars

app.py

@@ -16,7 +16,7 @@ from routes.export import export_bp # Import the new export blueprint
 from routes.tags import tags_bp # Import the new tags blueprint
 from routes.programs import programs_bp # Import the new programs blueprint
 from extensions import db
-from utils import convert_str_to_date, generate_plot
+from utils import convert_str_to_date
 from flask_htmx import HTMX
 import minify_html
 import os