Require suggestion before entering vote phase

Endpoints/StateEndpoints.cs

@@ -61,6 +61,17 @@ public static class StateEndpoints
             var reconciled = EndpointHelpers.ReconcilePlayerPhase(player, appState.ResultsOpen);
             var next = NextPhase(player.CurrentPhase);
 
+            if (next == Phase.Vote)
+            {
+                var hasSuggestions = await db.Suggestions.AnyAsync(s => s.PlayerId == player.Id);
+                if (!hasSuggestions)
+                {
+                    if (reconciled)
+                        await db.SaveChangesAsync();
+                    return EndpointHelpers.BadRequestError("Add at least one suggestion before entering the Vote phase.");
+                }
+            }
+
             if (next == Phase.Results && !appState.ResultsOpen)
             {
                 if (reconciled)
@@ -108,4 +119,3 @@ public static class StateEndpoints
         _             => Phase.Suggest
     };
 }
-