Add project files.

Features/Puzzle/List/ListPuzzlesEndpoint.cs

@@ -0,0 +1,43 @@
+using ConnectionsAPI.Database;
+using ConnectionsAPI.Models;
+using LazyCache;
+using Microsoft.EntityFrameworkCore;
+
+namespace ConnectionsAPI.Features.Puzzle.List
+{
+    public class ListPuzzlesEndpoint(ConnectionsContext db, IAppCache cache) : EndpointWithoutRequest<ICollection<PuzzleDTO>>
+    {
+        private readonly ConnectionsContext _db = db;
+        private readonly IAppCache _cache = cache;
+
+        public override void Configure()
+        {
+            Get("/all.json");
+            AllowAnonymous();
+        }
+
+        public override async Task HandleAsync(CancellationToken ct)
+        {
+            // get response from cache
+            var response = await _cache.GetOrAddAsync("Puzzle:All",
+                                                      GetResponseForCache,
+                                                      DateTimeOffset.UtcNow.AddMinutes(5));
+            // done
+            await SendAsync(response, cancellation: ct);
+        }
+
+        private async Task<ICollection<PuzzleDTO>> GetResponseForCache()
+        {
+            // query all, ordered by print date
+            var puzzles = await _db.Puzzles
+                .Include(x => x.Categories)
+                .ThenInclude(x => x.PuzzleCards)
+                .AsNoTracking()
+                .OrderBy(x => x.PrintDate)
+                .ToListAsync();
+
+            // map to dto
+            return puzzles.Select(PuzzleDTO.FromEntity).ToList();
+        }
+    }
+}