Add buttons, menus and the rest of M3 Expressive's actions

<x-button> (label buttons, icon buttons and toggles in five sizes, with
filled, tonal, outlined, elevated and text variants in any colour role),
<x-tooltip>, <x-menu> with items, groups and separators, <x-button-group>,
<x-group> as a connected button group, <x-split-button>, <x-fab>,
<x-fab-menu> and <x-loading>. Sizes, colours and shapes come from
androidx Compose Material 3's tokens; the loading indicator ports its
Morph into SVG + SMIL.

Menus follow WAI-ARIA's menu button pattern on popovers placed by CSS
anchor positioning. Browser tests run in Chromium, Firefox and WebKit.
The showcase fetches the icon names on demand: inlined, they tripped
Pest's test server into HTTP 431s under Firefox.

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

routes/showcase.php

@@ -5,4 +5,5 @@ use NoNameWeb\LivewireMaterial\Http\Controllers\ShowcaseSymbolController;
 
 Route::view('/', 'livewire-material::showcase.index')->name('showcase');
 
-Route::get('symbols/{style}/{name}.svg', ShowcaseSymbolController::class)->name('symbol');
+Route::get('symbols.json', [ShowcaseSymbolController::class, 'index'])->name('symbols');
+Route::get('symbols/{style}/{name}.svg', [ShowcaseSymbolController::class, 'show'])->name('symbol');