Fill a selected row written by hand in secondary-container again

1.x drew `data-selected` on any `data-list-row` that was not a card in
secondary-container with on-secondary-container ink, whatever element
the row was. 2.0.0 kept that only for `<x-list-item selected>` and a
table row's `aria-selected="true"`, so an application's own `<li>`,
`<div>` or `<tr>` with `data-md-list-row` and `data-md-selected` - the
contract list-rows.js still describes - lost its selected state without
a word. list-item.css now fills such a row, cards and list items
excluded, and names the fill `--md-list-row-fill`, so hover, focus and
press tint it as they tint a selected list item rather than replacing
it (1.x's selected fill hid them). In `<x-table>`, `data-md-selected`
selects a plain row too, beside `aria-selected="true"`, which ARIA
allows on a row only in a grid. A browser test compares a hand-made
selected `<li>` and a plain selected `<tr>` with the role pair in the
light and dark themes, checks that a selected card keeps its own fill
and that hover tints the row's fill; it fails without the change.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>

resources/boost/skills/livewire-material-development/SKILL.md

@@ -514,7 +514,7 @@ The `illustration` slot draws the application's own artwork in place of the shap
 
 `variant`: `filled` (default, surface-container-highest), `elevated`, `outlined`; medium corner. Props `title`, `subtitle`, `separator`, `heading` (the title's element, `h3` by default: pass `h2` for a card straight under the page's `h1`); slots `figure` (full-bleed media), `menu` (top-end), `actions` (end-aligned). A card holds content and actions about one subject (M3); a table of many rows or a group of settings is a headed section, not a card. Choose its fill with `variant`, not a background of your own.
 
-A card or list item that opens something is a **row**: `data-md-list-row` on it and `data-md-list-open` on its one opener (the title link or a button). A press anywhere else on the row reaches the opener; its other controls keep their own presses. Never wrap a card in `<a>` or use a stretched link. A row answers with the state layer and one step of elevation; its corner does not move.
+A card or list item that opens something is a **row**: `data-md-list-row` on it and `data-md-list-open` on its one opener (the title link or a button). A press anywhere else on the row reaches the opener; its other controls keep their own presses. Never wrap a card in `<a>` or use a stretched link. A row answers with the state layer and one step of elevation; its corner does not move. `data-md-selected` on a row that is not a card — your own `<li>`, `<div>` or `<tr>`, the one whose sheet is open — fills it secondary-container with on-secondary-container ink, the state layer over the fill (`<x-list-item selected>` writes it itself); a card takes no selected fill.
 
 ```blade
 <x-card variant="outlined" data-md-list-row wire:key="share-{{ $share->id }}">
@@ -1141,7 +1141,7 @@ A choice of colour profile (see Colour profiles): a swatch per generated profile
 
 ### `<x-table>`, `<x-sort-header>`
 
-A data table: write plain `<thead>`, `<tr>`, `<th>`, `<td>` inside `<x-table>`; the text classes on a cell (`md-text-end`, `md-nowrap`, `md-tabular`) always win over the table's own alignment. Rows are 52px — a target a finger can hit. `dense` tightens them to 36px and `size="xs"` is for a table inside a panel inside a panel (32px rows); M3 says density is always an opt-in, so neither is a default and both are yours to justify. Scrolling is yours: wrap it in an element that scrolls sideways (`overflow-x: auto` in your own CSS). A row that opens something is `data-md-list-row` with one `data-md-list-open` control; a selected row is `aria-selected="true"`.
+A data table: write plain `<thead>`, `<tr>`, `<th>`, `<td>` inside `<x-table>`; the text classes on a cell (`md-text-end`, `md-nowrap`, `md-tabular`) always win over the table's own alignment. Rows are 52px — a target a finger can hit. `dense` tightens them to 36px and `size="xs"` is for a table inside a panel inside a panel (32px rows); M3 says density is always an opt-in, so neither is a default and both are yours to justify. Scrolling is yours: wrap it in an element that scrolls sideways (`overflow-x: auto` in your own CSS). A row that opens something is `data-md-list-row` with one `data-md-list-open` control; a selected row is `data-md-selected`, or `aria-selected="true"` in a table that is a grid — the only place ARIA allows it on a row.
 
 `<x-sort-header column="size" :sort-by="$sortBy">Size</x-sort-header>` sorts through the Livewire property `sortBy` (`['column' => …, 'direction' => 'asc'|'desc']`; `model` names another), with `aria-sort`.