Making the header/title are a variable

Refactor Dockerfile and entrypoint script; add index.html.template and update example.env

scripts/entrypoint.sh

@@ -0,0 +1,7 @@
+#!/bin/sh
+# Process index.html.template to create index.html
+# Adjust the path if your template is located somewhere else
+envsubst < /templates/index.html.template > /templates/index.html
+
+# Start Gunicorn; using an environment variable for workers (default is 3)
+exec gunicorn --bind 0.0.0.0:8000 app:app --workers ${WORKERS:-3}