Enable offline caching for all web users

Previously, offline caching was conditionally enabled only for Hotwire
Native apps. This removes that restriction and enables offline support
for all users, including PWAs and regular browsers.

This Uses the new `fetchOptions` support in `TurboOffline` handlers
to pass `cache: "no-cache"` for document fetches, which we need
to work around a quite annoying Safari PWA bug
(see https://github.com/basecamp/fizzy/pull/1014).

Also, simplify a bit the cache names and remove the `misc` one.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Gemfile.lock

@@ -13,7 +13,7 @@ GIT
 
 GIT
   remote: https://github.com/hotwired/turbo-rails.git
-  revision: 45a2a40be0a677808a3a269311f1b5abaa3b30ba
+  revision: 9bcc244043b16ef0202f8fe93aaeb246d841f9eb
   branch: offline-cache
   specs:
     turbo-rails (2.0.21)