Add complete Laravel LLM Gateway implementation

Core Features:
- Multi-provider support (OpenAI, Anthropic, DeepSeek, Gemini, Mistral)
- Provider service architecture with abstract base class
- Dynamic model discovery from provider APIs
- Encrypted per-user provider credentials storage

Admin Interface:
- Complete admin panel with Livewire components
- User management with CRUD operations
- API key management with testing capabilities
- Budget system with limits and reset schedules
- Usage logs with filtering and CSV export
- Model pricing management with cost calculator
- Dashboard with Chart.js visualizations

Database Schema:
- MariaDB migrations for all tables
- User provider credentials (encrypted)
- LLM request logging
- Budget tracking and rate limiting
- Model pricing configuration

API Implementation:
- OpenAI-compatible endpoints
- Budget checking middleware
- Rate limit enforcement
- Request logging jobs
- Cost calculation service

Testing:
- Unit tests for all provider services
- Provider factory tests
- Cost calculator tests

Documentation:
- Admin user seeder
- Model pricing seeder
- Configuration files

laravel-app/routes/api.php

@@ -0,0 +1,27 @@
+<?php
+
+use Illuminate\Http\Request;
+use Illuminate\Support\Facades\Route;
+use App\Http\Controllers\Api\ChatCompletionController;
+
+/*
+|--------------------------------------------------------------------------
+| API Routes
+|--------------------------------------------------------------------------
+|
+| Here is where you can register API routes for your application. These
+| routes are loaded by the RouteServiceProvider and all of them will
+| be assigned to the "api" middleware group. Make something great!
+|
+*/
+
+Route::middleware('auth:sanctum')->group(function () {
+    // Chat Completion Endpoint
+    Route::post('/chat/completions', [ChatCompletionController::class, 'create'])
+        ->middleware(['checkbudget', 'checkratelimit']);
+    
+    // User info endpoint
+    Route::get('/user', function (Request $request) {
+        return $request->user();
+    });
+});