Add missing app files and fix Docker configuration

- Add all PHP app files (controllers, middleware, providers, models, enums)
  that were previously gitignored via app/.gitignore wildcard
- Fix app/.gitignore to no longer ignore all files
- Fix docker-compose.yml: use named volume for postgres to avoid chown permission errors on server
- Fix Dockerfile: use --classmap-authoritative for composer dump-autoload

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/Models/User.php

@@ -0,0 +1,34 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Foundation\Auth\User as Authenticatable;
+use Illuminate\Notifications\Notifiable;
+use Laravel\Sanctum\HasApiTokens;
+
+class User extends Authenticatable
+{
+    use HasApiTokens, Notifiable;
+
+    protected $fillable = [
+        'name',
+        'phone',
+        'password',
+        'avatar',
+        'status',
+        'role',
+        'balance',
+        'last_login',
+        'email_verified_at',
+    ];
+
+    protected $hidden = [
+        'password',
+        'remember_token',
+    ];
+
+    protected $casts = [
+        'email_verified_at' => 'datetime',
+        'last_login' => 'datetime',
+    ];
+}