Add the Material 3 Expressive foundation

Colour, shape, type, elevation and motion as tokens and Tailwind
utilities; `php artisan material:scheme`, which generates an app's colour
roles with Google's material-color-utilities (spec 2025); the theme head
script with light, dark and system and its Alpine store; Google Sans Flex;
every Material Symbol (4,135, outlined and filled) drawn by <x-icon>
without blade-icons; all 35 M3 Expressive shapes, ported from androidx, as
<x-shape>; the x-figure directive; the Toasts concern; DesignGuard for
applications' tests; and a showcase with every token, both themes side by
side and an icon search.

Colour utilities are `@theme inline`, so a section with its own
data-theme repaints; without it they resolve once on :root.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01V9NnLxnPp8vaaurb3Z1MFy

tests/Fixtures/design-guard/app/Status.php

@@ -0,0 +1,17 @@
+<?php
+
+namespace App;
+
+enum Status: string
+{
+    case Active = 'active';
+    case Expired = 'expired';
+
+    public function textClass(): string
+    {
+        return match ($this) {
+            self::Active => 'text-success',
+            self::Expired => 'text-red-500',
+        };
+    }
+}

tests/Fixtures/design-guard/views/page.blade.php

@@ -0,0 +1,9 @@
+{{-- <x-mary-button> and btn-primary in a comment are not violations --}}
+<x-mary-button label="Old" />
+<div class="card bg-base-200 p-4">
+    <x-icon name="o-home" />
+    <x-button icon="calendar_month" icon-right="not_a_symbol" label="Fine" />
+    <span @class(['btn-primary' => $active, 'select-none'])>text-red-600</span>
+    <p class="text-tertiary table collapse link focus-ring">Tailwind's and ours</p>
+    <x-icon :name="$dynamic" />
+</div>