Pin the two-line snackbar, and reach it with Alt+G

Plan step 22, actions.md § Missing (two-line snackbar height, snackbar
keyboard shortcut): the container grew organically from `min-h-12` rather
than sitting at SnackbarTokens.TwoLinesContainerHeight, and there was no
way for a keyboard to reach an actioned snackbar at all.

A `description` is M3's second line, so the snackbar is pinned to 68px
whenever one is there, and below `medium` a two-line snackbar with an
action wraps the action under the text — M3's "two lines with longer
action" configuration. Alt+G, the shortcut M3 suggests for the web, moves
the focus to a snackbar that carries an action from wherever the page had
it; `event.code`, because Alt rewrites `event.key` on some layouts.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Qwx5USif3wFFmxtHg5U1g9

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

@@ -364,7 +364,8 @@ window.dispatchEvent(new CustomEvent('toast', { detail: { type: 'info', title: '
 window.addEventListener('app:update', () => location.reload())
 ```
 
-- Escape dismisses a snackbar that holds the focus.
+- `description` is M3's second line: the container goes from 48px to 68px (`SnackbarTokens.TwoLinesContainerHeight`), and below `medium` a two-line snackbar with an action wraps the action under the text.
+- Escape dismisses a snackbar that holds the focus, and **Alt+G** moves the focus to a snackbar that carries an action from wherever the page had it — M3 asks the web for a documented shortcut of that kind, since a snackbar never takes the focus itself. Say so where your users read about keyboard shortcuts.
 - Hooks: `data-toast` on the snackbar on screen, `data-toast-action` on its action button (`[data-toast]` is absent while nothing shows). Target these in tests, not classes.
 
 ### `<x-progress>`