## Change 1 - database errors when running autosave
The previous autosave implementation allowed multiple autosave fetch
calls (=> save document draft) to run in parallel. While the
AbortController aborted previous autosave calls if a new one comes in in
order to only process the latest one, this had one flaw:
Using the AbortController to abort the autosave call only aborted the
`fetch` call - it did not however abort the database operation that may
have started as part of this fetch call. If you then started a new
autosave call, this will start yet another database operation on the
backend, resulting in two database operations that would be running at
the same time.
This has caused a lot of transaction errors that were only noticeable
when connected to a slower, remote database. This PR removes the
AbortController and ensures that the previous autosave operation is
properly awaited before starting a new one, while still discarding
outdated autosave requests from the queue **that have not started yet**.
Additionally, it cleans up the AutoSave component to make it more
readable.
## Change 2 - ensure autosave doesn't run unnecessarily
If connected to a slower backend or database, one change in a document
may trigger two autosave operations instead of just one. This is how it
could happen:
1. Type something => formstate changes => autosave is triggered
2. 200ms later: form state request is triggered. Autosave is still
processing
3. 100ms later: form state comes back from server => local form state is
updated => another autosave is triggered
4. First autosave is aborted - this lead to a browser error. This PR
ensures that that error is no longer surfaced to the user
5. Another autosave is started
This PR adds additional checks to ONLY trigger an autosave if the form
DATA (not the entire form state itself) changes. Previously, it ran
every time the object reference of the form state changes. This includes
changes that do not affect the form data, like `field.valid`. =>
Basically every time form state comes back from the server, we were
triggering another, unnecessary autosave
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