Replace hand-rolled auth with Laravel Breeze (Livewire stack)

Adds the auth Breeze scaffolds that were missing before: password
reset and email verification, plus a profile page (update name/email,
change password, delete account). User now implements MustVerifyEmail
so verification is actually enforced, not just scaffolded.

This does mean accepting Tailwind v3 (postcss/tailwind.config.js)
over the v4 CSS-first setup the app started with, and Livewire drops
from ^4.3 to ^3.6.4 — both forced by Breeze/Volt's current
compatibility requirements. Restored the Instrument Sans font Breeze's
installer dropped so styling stays close to what we had.

Reconciliation, since Breeze's installer assumes a blank-slate app:
- Deleted the hand-rolled Login/Register Livewire components/views/
  test — superseded by Breeze's Volt-based auth pages
  (resources/views/livewire/pages/auth/*), which also cover
  forgot-password, reset-password, verify-email, and confirm-password.
- Deleted Breeze's own default welcome/dashboard views and its
  separate app layout + nav component — kept our existing
  components/layouts/app.blade.php as the one real app layout, used
  Breeze's minimal layouts/guest.blade.php only for the auth pages.
- Rewrote routes/web.php merging our routes (home, sites, discover)
  with routes/auth.php; replaced every hardcoded route('dashboard')
  reference (5 Blade files plus, easy to miss, a plain PHP controller
  VerifyEmailController) with sites.index.
- Logout: Breeze's Actions\Logout::__invoke() returns void, so wired
  directly as a route it silently no-ops instead of redirecting;
  fixed with a thin closure that calls it then redirects.
- Fixed Breeze's own generated tests (Auth/AuthenticationTest,
  RegistrationTest, EmailVerificationTest, PasswordConfirmationTest)
  where they assumed the deleted dashboard route/nav component.

Verified: full suite (28 tests, including Breeze's Registration/
Authentication/PasswordReset/PasswordConfirmation/PasswordUpdate/
EmailVerification/Profile tests plus our own GuestPreviewTest) passes
against the huginn_testing MySQL database. Also smoke-tested for real:
all key pages return 200, /profile redirects guests to /login, guest
preview capping still works, and a real password-reset email was
generated and logged with correct branding and a working link.

resources/views/livewire/profile/delete-user-form.blade.php

@@ -0,0 +1,79 @@
+<?php
+
+use App\Livewire\Actions\Logout;
+use Illuminate\Support\Facades\Auth;
+use Livewire\Volt\Component;
+
+new class extends Component
+{
+    public string $password = '';
+
+    /**
+     * Delete the currently authenticated user.
+     */
+    public function deleteUser(Logout $logout): void
+    {
+        $this->validate([
+            'password' => ['required', 'string', 'current_password'],
+        ]);
+
+        tap(Auth::user(), $logout(...))->delete();
+
+        $this->redirect('/', navigate: true);
+    }
+}; ?>
+
+<section class="space-y-6">
+    <header>
+        <h2 class="text-lg font-medium text-gray-900 dark:text-gray-100">
+            {{ __('Delete Account') }}
+        </h2>
+
+        <p class="mt-1 text-sm text-gray-600 dark:text-gray-400">
+            {{ __('Once your account is deleted, all of its resources and data will be permanently deleted. Before deleting your account, please download any data or information that you wish to retain.') }}
+        </p>
+    </header>
+
+    <x-danger-button
+        x-data=""
+        x-on:click.prevent="$dispatch('open-modal', 'confirm-user-deletion')"
+    >{{ __('Delete Account') }}</x-danger-button>
+
+    <x-modal name="confirm-user-deletion" :show="$errors->isNotEmpty()" focusable>
+        <form wire:submit="deleteUser" class="p-6">
+
+            <h2 class="text-lg font-medium text-gray-900 dark:text-gray-100">
+                {{ __('Are you sure you want to delete your account?') }}
+            </h2>
+
+            <p class="mt-1 text-sm text-gray-600 dark:text-gray-400">
+                {{ __('Once your account is deleted, all of its resources and data will be permanently deleted. Please enter your password to confirm you would like to permanently delete your account.') }}
+            </p>
+
+            <div class="mt-6">
+                <x-input-label for="password" value="{{ __('Password') }}" class="sr-only" />
+
+                <x-text-input
+                    wire:model="password"
+                    id="password"
+                    name="password"
+                    type="password"
+                    class="mt-1 block w-3/4"
+                    placeholder="{{ __('Password') }}"
+                />
+
+                <x-input-error :messages="$errors->get('password')" class="mt-2" />
+            </div>
+
+            <div class="mt-6 flex justify-end">
+                <x-secondary-button x-on:click="$dispatch('close')">
+                    {{ __('Cancel') }}
+                </x-secondary-button>
+
+                <x-danger-button class="ms-3">
+                    {{ __('Delete Account') }}
+                </x-danger-button>
+            </div>
+        </form>
+    </x-modal>
+</section>