checkAuthentication() used await for the OIDC exchange fetch but was
declared as a regular function, not async. This caused a JavaScript
syntax error that prevented the entire app.js file from parsing,
resulting in a completely non-interactive frontend after OIDC login.
Also bumped service worker cache version to v2 so browsers
discard stale cached JS files on the next load.
Dionisio
177f82ca16
