added auth with a simple UI

api/OED.Api/Infrastructure/Auth/SessionMiddleware.cs

@@ -0,0 +1,23 @@
+using OED.Api.Core.Interfaces.Services;
+
+namespace OED.Api.Infrastructure.Auth;
+
+// Runs on every request — reads the session cookie and stamps CharacterId onto HttpContext.Items
+public class SessionMiddleware(RequestDelegate next)
+{
+    public async Task InvokeAsync(HttpContext context, ISessionService sessionService)
+    {
+        if (context.Request.Cookies.TryGetValue("session", out var sessionId))
+        {
+            var session = await sessionService.GetAsync(sessionId);
+            if (session is not null)
+            {
+                context.Items["CharacterId"] = session.CharacterId;
+                context.Items["CharacterName"] = session.CharacterName;
+                context.Items["Session"] = session;
+            }
+        }
+
+        await next(context);
+    }
+}