Refactor payment verification to manual workflow and add comprehensive cleanup tools

Major changes:
• Remove BTCPay Server integration in favor of SilverPAY manual verification
• Add test data cleanup mechanisms (API endpoints and shell scripts)
• Fix compilation errors in TestController (IdentityReference vs CustomerIdentity)
• Add deployment automation scripts for Hostinger VPS
• Enhance integration testing with comprehensive E2E validation
• Add Blazor components and mobile-responsive CSS for admin interface
• Create production environment configuration scripts

Key Features Added:
• Manual payment verification through Admin panel Order Details
• Bulk test data cleanup with proper cascade handling
• Deployment automation with systemd service configuration
• Comprehensive E2E testing suite with SilverPAY integration validation
• Mobile-first admin interface improvements

Security & Production:
• Environment variable configuration for production secrets
• Proper JWT and VAPID key management
• SilverPAY API integration with live credentials
• Database cleanup and maintenance tools

🤖 Generated with Claude Code

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

LittleShop/Areas/Admin/Controllers/ProductsController.cs

@@ -27,11 +27,17 @@ public class ProductsController : Controller
         Response.Headers.Add("Cache-Control", "no-cache, no-store, must-revalidate");
         Response.Headers.Add("Pragma", "no-cache");
         Response.Headers.Add("Expires", "0");
-        
+
         var products = await _productService.GetAllProductsAsync();
         return View(products);
     }
 
+    public IActionResult Blazor(Guid? id)
+    {
+        ViewData["ProductId"] = id;
+        return View();
+    }
+
     public async Task<IActionResult> Create()
     {
         var categories = await _categoryService.GetAllCategoriesAsync();