feat: complete mealplanner app (backend + frontend + deployment)

.NET 8 backend with Zitadel JWT auth, TheMealDB integration,
weekly meal plan generation, shopping list aggregation.
Vue 3 + Tailwind 4 frontend with dark emerald theme,
manual OIDC PKCE auth, all views implemented.
Multi-stage Dockerfile with nginx reverse proxy.

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

backend/Controllers/ShoppingListController.cs

@@ -0,0 +1,45 @@
+using Microsoft.AspNetCore.Authorization;
+using Microsoft.AspNetCore.Mvc;
+using MealPlanner.Services;
+
+namespace MealPlanner.Controllers;
+
+[ApiController]
+[Route("api/shoppinglist")]
+[Authorize]
+public class ShoppingListController(ShoppingListService shoppingListService) : ControllerBase
+{
+    private string UserId => User.FindFirst("sub")?.Value ?? throw new UnauthorizedAccessException();
+
+    [HttpGet("{mealPlanId:guid}")]
+    public async Task<IActionResult> GetList(Guid mealPlanId)
+    {
+        try
+        {
+            var items = await shoppingListService.GetShoppingListAsync(mealPlanId, UserId);
+            return Ok(items);
+        }
+        catch (UnauthorizedAccessException)
+        {
+            return Forbid();
+        }
+    }
+
+    [HttpPut("{mealPlanId:guid}/check/{itemName}")]
+    public async Task<IActionResult> ToggleCheck(Guid mealPlanId, string itemName)
+    {
+        try
+        {
+            var result = await shoppingListService.ToggleCheckAsync(mealPlanId, itemName, UserId);
+            return Ok(result);
+        }
+        catch (KeyNotFoundException ex)
+        {
+            return NotFound(ex.Message);
+        }
+        catch (UnauthorizedAccessException)
+        {
+            return Forbid();
+        }
+    }
+}