feat: add City10 platform with Laravel 13, AI agents, 3D viewer, and LGPD compliance

Initial commit of the complete City10 virtual city simulation platform.

Backend (Laravel 13):
- REST API with Sanctum tokens and session-based web authentication
- Role-based access control (admin/user) with middleware protection
- AI agent CRUD with OpenRouter.ai integration restricted to free models
- Store management with 3D coordinates and AI shopkeeper assignment
- Versioned legal documents (Terms, Privacy, Cookies) with LGPD audit trail
- Math CAPTCHA on public forms and multi-language support (pt_BR, en, es)

Frontend:
- Responsive Blade templates with Tailwind CSS v4
- Three.js 3D city viewer with SSE chat streaming to AI agents
- Admin panel for store and user administration

Infrastructure:
- MariaDB/MySQL database with comprehensive migrations
- Database seeders for demo content and test accounts
- PHPUnit test suite and Laravel Pint code styling
- Vite build configuration with hot reload

app/Http/Requests/AiAgentRequest.php

@@ -0,0 +1,60 @@
+<?php
+
+namespace App\Http\Requests;
+
+use Illuminate\Contracts\Validation\ValidationRule;
+use Illuminate\Foundation\Http\FormRequest;
+use Illuminate\Validation\Rule;
+
+/**
+ * Validates creation and update payloads for AI agents.
+ *
+ * Enforces the allow-list of free OpenRouter models defined in
+ * config/ai.php so that no paid model can ever be activated.
+ */
+class AiAgentRequest extends FormRequest
+{
+    /**
+     * Determine if the user is authorized to make this request.
+     */
+    public function authorize(): bool
+    {
+        // Authorization is enforced by admin role middleware in routes.
+        return $this->user()?->isAdmin() ?? false;
+    }
+
+    /**
+     * Get the validation rules that apply to the request.
+     *
+     * @return array<string, ValidationRule|array<mixed>|string>
+     */
+    public function rules(): array
+    {
+        $allowed = config('ai.allowed_models', []);
+
+        return [
+            'name' => ['required', 'string', 'max:120'],
+            'type' => ['required', 'string', 'max:40'],
+            'model' => ['required', 'string', Rule::in($allowed)],
+            'system_prompt' => ['nullable', 'string', 'max:8000'],
+            'current_goal' => ['nullable', 'string', 'max:2000'],
+            'status' => ['nullable', Rule::in(['active', 'paused', 'thinking', 'error'])],
+            'pos_x' => ['nullable', 'numeric', 'between:-100000,100000'],
+            'pos_y' => ['nullable', 'numeric', 'between:-100000,100000'],
+            'pos_z' => ['nullable', 'numeric', 'between:-100000,100000'],
+            'rotation_y' => ['nullable', 'numeric', 'between:-6.2832,6.2832'],
+        ];
+    }
+
+    /**
+     * Get custom messages for validation errors.
+     *
+     * @return array<string, string>
+     */
+    public function messages(): array
+    {
+        return [
+            'model.in' => __('validation.model_not_allowed'),
+        ];
+    }
+}