Add some basic offline support

config/urls.py-tpl

@@ -11,6 +11,15 @@ from core.forms import RegisterForm
 urlpatterns = [
     path("", views.placeholder, name="index"),
     path("private-page", views.private_page, name="private-page"),
+    # PWA goodies
+    path(
+        "sw.js",
+        TemplateView.as_view(
+            template_name="js/sw.js", content_type="application/javascript"
+        ),
+        name="sw",
+    ),
+    path("offline", TemplateView.as_view(template_name="offline.html"), name="offline"),
     path("favicon.ico", views.favicon),
     # Redirect the old registration URL.
     path(

documentation/index.md

@@ -21,3 +21,13 @@ However, if you still want to use Tailwind (no judgement), here's how you can do
 - [Fly](deployment/fly.md)
 
 Why no AWS? We don't believe you should use it. We do our best to not give Amazon any money if we can help it.
+
+## Update Workbox
+
+- `npx workbox-cli copyLibraries static/js/vendor/`
+- Update paths in `templates/js/sw.js` as needed.
+
+Further reading:
+
+- [Using Local Workbox Files Instead of CDN](https://developer.chrome.com/docs/workbox/modules/workbox-sw/#using-local-workbox-files-instead-of-cdn)
+- [workbox-cli’s copylibraries option](https://developer.chrome.com/docs/workbox/modules/workbox-cli/#copylibraries)