CI/CD: Add GitLab CI/CD pipeline for Hostinger deployment

- Updated .gitlab-ci.yml with complete build, test, and deploy stages
- Added authentication redirect fix in Program.cs (302 redirect for admin routes)
- Fixed Cookie vs Bearer authentication conflict for admin panel
- Configure pipeline to build from .NET 9.0 source
- Deploy to Hostinger VPS with proper environment variables
- Include rollback capability for production deployments

🤖 Generated with Claude Code

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

LittleShop/Program.cs

@@ -140,12 +140,33 @@ if (string.IsNullOrEmpty(jwtKey))
 var jwtIssuer = builder.Configuration["Jwt:Issuer"] ?? "LittleShop";
 var jwtAudience = builder.Configuration["Jwt:Audience"] ?? "LittleShop";
 
-builder.Services.AddAuthentication("Cookies")
+builder.Services.AddAuthentication(options =>
+    {
+        options.DefaultScheme = "Cookies";
+        options.DefaultChallengeScheme = "Cookies";
+    })
     .AddCookie("Cookies", options =>
     {
         options.LoginPath = "/Admin/Account/Login";
         options.LogoutPath = "/Admin/Account/Logout";
         options.AccessDeniedPath = "/Admin/Account/AccessDenied";
+        options.Events = new Microsoft.AspNetCore.Authentication.Cookies.CookieAuthenticationEvents
+        {
+            OnRedirectToLogin = context =>
+            {
+                // For admin routes, always redirect to login page
+                if (context.Request.Path.StartsWithSegments("/Admin"))
+                {
+                    context.Response.StatusCode = 302;
+                    context.Response.Headers["Location"] = context.RedirectUri;
+                    return Task.CompletedTask;
+                }
+
+                // For API routes, return 401
+                context.Response.StatusCode = 401;
+                return Task.CompletedTask;
+            }
+        };
     })
     .AddJwtBearer("Bearer", options =>
     {
@@ -166,7 +187,7 @@ builder.Services.AddAuthorization(options =>
     options.AddPolicy("AdminOnly", policy =>
         policy.RequireAuthenticatedUser()
               .RequireRole("Admin")
-              .AddAuthenticationSchemes("Cookies", "Bearer")); // Support both cookie and JWT
+              .AddAuthenticationSchemes("Cookies")); // Only use cookies for admin panel
     options.AddPolicy("ApiAccess", policy =>
         policy.RequireAuthenticatedUser()
               .AddAuthenticationSchemes("Bearer")); // JWT only for API access