add auto refresh to dags home page

[talnagar]

Add auto refresh functionality to the home page (dags).
closes: #22418

refresh every 2 seconds:

• last dag runs
• last run
• recent tasks

---

before:

after:

[talnagar]

@bbovenzi I would appreciate your feedback on this.
In addition, I didn't know whether there are any tests relevant for ui only changes such as this.
thanks.

[bbovenzi]

Looking great! A few comments

• Let's avoid refreshing when the page isn't focused (see graph.js)
• The formatting of the loading dots and auto-refresh text breaks on screens below 1380px in width. Let's change the .refresh-actions > .switch-label { in main.css to margin: 0 10px;
• In grid and graph, we turn off refresh when there are no longer any active runs. I wonder if we should something similar here or at least increase the refresh interval.

[talnagar]

@bbovenzi thanks for the review.
As suggested

• paused the refresh when the page isn't focused
• unchecked auto refresh when there are no more active runs
• I changed the css and template layout a bit so it won't break, hopefully now it looks better on all screen sizes.

[bbovenzi]

Let's still fix the margin for the switch. Even with removing that classname, this still happens:

[talnagar]

@bbovenzi for some reason I can't reproduce this break. I removed the margin now hopefully it looks ok.

[bbovenzi]

Great work! I think people will be really excited to have this.

But let's not merge until 2.3.0b1 is out

[talnagar]

Great work! I think people will be really excited to have this.

But let's not merge until 2.3.0b1 is out

Thanks @bbovenzi! 😃

[github-actions]

The PR is likely OK to be merged with just subset of tests for default Python and Database versions without running the full matrix of tests, because it does not modify the core of Airflow. If the committers decide that the full tests matrix is needed, they will add the label 'full tests needed'. Then you should rebase to the latest main or amend the last commit of the PR, and push it with --force-with-lease.

[talnagar]

@bbovenzi can this be merged now?

[marclamberti]

OMG! this is AWESOME ❤️