Remove query cancellation from StateManagers

[bcolloran]

experiment with removing query cancellation

Here's what I see in a couple conditions

(1) state as of changes in this PR:

• all manually query cancellation removed
• observeContextColumnWidth reactive statement commented out

Results:

• everything above the fold loads in about 15 seconds,
• loading keeps going for stuff below the fold
• no queries cancelled

firefox_DpIsohhvGJ.mp4

(2) Main before this PR, but without observeContextColumnWidth

• manual query cancellation in place
• observeContextColumnWidth reactive statement commented out

Results:

• everything above the fold loads in about 15 seconds,
• loading keeps going for stuff below the fold
• no queries cancelled
  https://github.com/rilldata/rill/assets/2380975/194cfdfc-769a-4fdb-9acb-ad7b5d115205

[ericpgreen2]

It doesn't appear like these cancelQueries calls are adding any value to the dashboard. Out-of-the-box query cancellation works just fine without these explicit calls. Can you go ahead and remove the calls and related code?

However, for now can you keep the calls in ModelBody.svelte and resource-invalidations.ts? IIRC those are there as a ham-fisted way to cancel/invalidate outstanding queries.

[bcolloran]

@AdityaHegde and @djbarnwal would love to get your takes on this also before we go forward with any changes.

@ericpgreen2 and I have been looking at query cancellation in the context of https://github.com/rilldata/rill-private-issues/issues/112, and think that we might be doing extra manual cancellations in places where tanstack should be able to do that automatically. I think that as a team, we need to audit all of those manual cancellation and understand why they are needed, and if they can be removed.

@AdityaHegde, I've assigned this to you because I think you probably know the most about the intersection between runtime and client here. I think "done" on this would be code comments for any places we want to retain manual query cancellation. I don't mind making the changes in this PR if you just want to put those comments as review comments.

[djbarnwal]

I haven't personally worked a lot with query cancellation and relied on tanstack for it. I am up for removing manual cancellation if they don't have any performance implications.

[AdityaHegde]

We need these since there could be a race condition in request for profile sent and added to queue in backend vs the entity being deleted.

[AdityaHegde]

Same applies to line 158 and line 99 in ModelBody.

[bcolloran]

@ericpgreen2 cleaning this up to get it over the line -- removed changes in ModelBody.svelte and resource-invalidations.ts, per you and @AdityaHegde's suggestions

[ericpgreen2]

Great. Looks like a good low-risk cleanup.