Browser back navigation creates desync local and server state after disposition edit

[geromequa]

Describe the bug
After editing the disposition of a shift, the dispostion edit view is still in browser history. When navigating back to the event overview by using the back navigation twice, the local state, i.e., the changed disposition, is reverted back. After reloading the page server-side-state updates the local state accordingly

To Reproduce
Steps to reproduce the behavior:

1. Go to 'https://shifts.myhpi.de/events/181-hutmensch/' (or equivalent event overview)
2. Click on 'Disposition'
3. Change anything (for example decline a user)
4. Save the Changes.
5. Navigate back using browser back button twice (you should arrive back on the overview)
6. The disposition change is reverted in displayed UIExpected behavior
   After editing a disposition, event or similar the edit-view gets removed from the browser navigation history.
7. Reload the page (should update back to server-side-state

Expected Behavior
The "Edit"-view should be removed from the browser navigation history.

Environment
Fedora Linux 44, Firefox

[felixrindt]

This is the default behaviour for MPA (multi page applications) with the backwards-forwards-cache in todays webbrowsers. The 'outdated' page is served from memory when the user navigates back. After researching, I found that

• sites like Github tend to show the same behavior.
• for data protection reasons, we should add a Cache Control header that disallows storing our sites in the cache, as the almost always contain nonpublic data.
• We could (selectively for the PWA) force reloading when using the bfcache, which would prevent outdated states being shown, but would otherwise destroy the performance benefit of having the bfcache at all. Maybe there is some clever way to only force a reload in some szenarios, but as we have multiple views showing the same state (e.g. disposition and event detail), I find that hard to come up with.

I created a PR with the change, please try and report how it feels to you: