feat: Implement client authentication and pre-fill functionality

- Added AuthController for client login and token management.
- Introduced AuthGate for handling authentication state and login UI.
- Updated API to support fetching client data for pre-filling forms.
- Modified App.vue to pre-fill client information if logged in.
- Enhanced client model to include username and password fields.
- Created migration for adding username and password to clients table.
- Added utility for generating secure usernames and passwords.
- Updated frontend to handle client tokens for pre-filling checkout forms.
- Removed old CSS file and updated HTML references to new assets.
- Added StatsOverview widget for displaying client and quote statistics.
- Improved error handling and user feedback in the login process.

backoffice/resources/views/filament/infolists/cliente-password-reveal.blade.php

@@ -0,0 +1,35 @@
+@php $passwordJs = \Illuminate\Support\Js::from($password); @endphp
+<div
+    x-data="{ copied: false }"
+    class="rounded-lg border border-warning-300 bg-warning-50 p-4 dark:border-warning-800 dark:bg-warning-950"
+>
+    <p class="text-sm font-medium text-warning-800 dark:text-warning-200">
+        Copia subito la password: per motivi di sicurezza non sarà più possibile visualizzarla in seguito.
+    </p>
+
+    <dl class="mt-3 grid grid-cols-[max-content_1fr] items-center gap-x-4 gap-y-2 text-sm">
+        <dt class="text-gray-500 dark:text-gray-400">Nome utente</dt>
+        <dd class="font-mono font-medium">{{ $username }}</dd>
+        <dt class="text-gray-500 dark:text-gray-400">Password</dt>
+        <dd class="rounded bg-white px-2 py-1 font-mono dark:bg-gray-900">{{ $password }}</dd>
+    </dl>
+
+    <x-filament::button
+        type="button"
+        color="warning"
+        size="sm"
+        class="mt-3"
+        x-on:click="
+            navigator.clipboard.writeText({{ $passwordJs }});
+            copied = true;
+            setTimeout(() => (copied = false), 2000);
+            new FilamentNotification()
+                .title('Password copiata negli appunti')
+                .success()
+                .send();
+        "
+    >
+        <span x-show="!copied">Copia password</span>
+        <span x-show="copied" x-cloak>Copiata!</span>
+    </x-filament::button>
+</div>