[ML] Data Frame Analytics: Improve analysis progress in job list

[walterra]

Follow up to #65305.

The above PR introduced progress reporting for data frame analytics that includes information about individual analysis steps (current step/total steps) and a progress bar showing progress as % of the current step.

We want to improve the wording and fine-tune the layout:

The column header needs to be brief but still needs to explain what the combination of steps + progress is about. Options we have: Tweak the wording to have a short header that explains everything (not that easy?). Alternative: Just show something like "Progress" as the heading and add an info icon + tooltip for a better explanation.

Some alternatives:

Heading just "Progress" and Steps in front of progress bar:

Heading just "Progress" with Info-Tooltip in front of progress bar without percentage text (could be visible on hover)

Note, additionally the user can always expand a row to investigate progress in more detail.

I also thought about splitting steps and progress into two table columns, but that wouldn't allow a user to sort the table by overall progress, just by either steps or progress of step.

[elasticmachine]

Pinging @elastic/ml-ui (:ml)

[peteharverson]

I prefer both these options to the current Progress per Step heading. Also good to have it in one column rather than two, for the sorting reason you mention.

Some thoughts - I wonder if we need to say Step 3 of 4, rather than 3/4 , which could give the impression that the job was 75% done!? But that would be a fair bit more text for that column. Not showing the percentage value would free up some space I guess.

The info icon would help, but isn't there an issue with sorting when the column header contains non-text content?

[walterra]

Summarizing some feedback:

• Needs clear visual clues that the progress relates to a step, not the whole job, tooltip might be too subtle. (Note that while the wording might not have been perfect, that was the intention of the original column heading "Progress per Step")
• Text in each row like Step 1/4 might add clarity (but will add redundant boilerplate text)
• Overall sentiment leans towards Step 1/4 [ProgressBar] including a tooltip for the progress bar:

With Phase instead of Step: