Grid layout: revamp the design to make it usable

[priethor]

What

Part of #103.

This PR turns the grid into a layout we can actually use for browsing. Cards open rows when clicked, expose the same row actions as the table, let visible properties be edited, and include a New card at the end of the grid. Switching between table, grid, and list keeps the current search, filters, sort, pagination, and layout settings. The seed data now opens Music Catalog > Albums as a grid, with some cards showing covers and some left plain.

Why

Grid was the roughest part of the DataView baseline; this gets it to a decent first pass. The list layout is still next, on a separate PR.

How

• Keeps each layout's settings separate so table, grid, and list do not overwrite each other.
• Builds on the native DataViews grid instead of replacing it.
• Adds cover data to rows so cards can show images.
• Uses grid-shaped loading states instead of table-shaped placeholders.

Testing Instructions

1. Open a seeded workspace and go to Music Catalog. Albums should render as a grid with a mix of covered and plain cards.
2. Switch a collection from table to grid to list and back to table. Search, filters, sort, pagination, and layout settings should survive.
3. In the grid, click a card to open the row. Use the row menu to duplicate, favorite, and trash it.
4. Add a visible property in the grid, then hover or keyboard-focus the value and edit it.
5. Add a new row from the grid. New should appear as a card in the grid.

Screen recording

Grabacion.de.pantalla.2026-05-27.a.las.11.17.08.mov