Polish DataView block layout

[priethor]

What

Polishes the embedded data-view block layout. Short tables now hug their content instead of sitting inside a fixed 640px box, and long tables can keep growing with the document. The block selection outline also stays visible around the table, pagination, and New row button.

This also tightens the actions column so it only takes the space needed for the kebab / + controls, and keeps shorter cells centered when another cell makes the row taller.

Why

Small embedded tables looked oddly tall, and the pagination footer could cut through Gutenberg's blue selection outline. The actions column had a similar polish issue: it inherited the generic table-cell width, which wasted space and could push real data under the sticky-right edge.

Testing Instructions

1. Add or select a cortext/data-view block with a short collection.
2. Check that the block height fits the visible rows without a large empty area.
3. Select the block and check that the blue outline stays continuous around the table, pagination, and New row button.
4. Check that the actions column is only wide enough for the kebab / + controls.
5. Use a row with taller wrapped content and check that shorter cells and row controls stay vertically centered.
6. Open a full collection view and check that the table still scrolls normally there.

Screenshots

Before	After