feat(auth): block admin login IP after 4 failures for 20 min, email login alerts

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

database/migrations/2026_10_23_000001_create_admin_login_blocks_table.php

@@ -0,0 +1,26 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration {
+    public function up(): void
+    {
+        Schema::create('admin_login_blocks', function (Blueprint $table) {
+            $table->id();
+            $table->string('ip', 45)->unique();
+            $table->unsignedInteger('failed_attempts')->default(0);
+            $table->string('last_username', 191)->nullable();
+            $table->string('user_agent', 500)->nullable();
+            $table->timestamp('last_failed_at')->nullable();
+            $table->timestamp('blocked_until')->nullable()->index();
+            $table->timestamps();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('admin_login_blocks');
+    }
+};

database/migrations/2026_10_23_000002_seed_admin_login_alert_template.php

@@ -0,0 +1,17 @@
+<?php
+
+use Database\Seeders\TemplateSeeder;
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\DB;
+
+return new class extends Migration {
+    public function up(): void
+    {
+        (new TemplateSeeder())->seedScenarioIfMissing('admin_login_alert');
+    }
+
+    public function down(): void
+    {
+        DB::table('template')->where('scenario', 'admin_login_alert')->delete();
+    }
+};