[EuiDataGrid] Make popover size configureable

[kertal]

Currently the size of the popover is static with a max height and width of 400px. This might be sufficient for lot's of cases, but given the variety of field values e.h. in Discover it would be awesome if this would be configureable. Currently it's like that:

eui/src/components/datagrid/_data_grid_data_row.scss

Lines 100 to 107 in 91368b5

	.euiDataGridRowCell__popover {
	@include euiScrollBar;
	overflow: auto;
	// sass-lint:disable-block no-important
	max-width: 400px !important;
	max-height: 400px !important;
	z-index: $euiZDataGridCellPopover !important;
	}

Here's an example where more vertical screen space would make sense in Discover:

Of course this depends on the available screen size, so it should be responsive.

There could be configureable like this

• static max height/width
• responsive (optimized for screen space)
• a function to allow the consuming application to return custom height/width
• user could manually resize (somewhere in the future)

[cee-chen]

Worth considering how this would work with #5686 (if we place the popover directly over the cell in the future)

[github-actions]

👋 Hey there. This issue hasn't had any activity for 180 days. We'll automatically close it if that trend continues for another week. If you feel this issue is still valid and needs attention please let us know with a comment.

[kertal]

I still think this would be valuable

[github-actions]

👋 Hi there - this issue hasn't had any activity in 6 months. If the EUI team has not explicitly expressed that this is something on our roadmap, it's unlikely that we'll pick this issue up. We would sincerely appreciate a PR/community contribution if this is something that matters to you! If not, and there is no further activity on this issue for another 6 months (i.e. it's stale for over a year), the issue will be auto-closed.

[github-actions]

❌ Per our previous message, this issue is auto-closing after having been open and inactive for a year. If you strongly feel this is still a high-priority issue, or are interested in contributing, please leave a comment or open a new issue linking to this one for context.