refactor: refine shop plugin models, migrations, resources and config

Comprehensive refinement of the shop package including:
- Update all models with proper casts, relationships and table prefixing
- Modernize all migration stubs with consistent naming and structure
- Improve Filament resource forms, infolists and tables
- Add tax rate minimum value validation (must be > 0)
- Center-align orders count column in customer table
- Add AddressObserver, InvoiceRelationManager and OrderRelationManager
- Fix categoriable -> categorizable typo in migration
- Update config with table prefix support
- Fix RecordUserLogin to handle nullable userId

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: mhortulanus

src/Jobs/RecordUserLogin.php

@@ -13,8 +13,8 @@ class RecordUserLogin implements ShouldQueue
      * @param  array<string, mixed>|null  $inputs
      */
     public function __construct(
-        public int $userId,
-        public string $type,
+        public ?int $userId,
+        public ?string $type,
         public ?string $url,
         public ?string $referrer,
         public ?array $inputs,
@@ -24,6 +24,10 @@ public function __construct(
 
     public function handle(): void
     {
+        if(!$this->userId) {
+            return;
+        }
+
         $userModel = config('users.eloquent.user.model');
 
         if (! $userModel || ! class_exists($userModel)) {