AreaComAdminWindow: Allow users to create new reeds inline

Elwig/Helpers/AppDbContext.cs

@@ -163,6 +163,13 @@ namespace Elwig.Helpers {
             return c + 1;
         }
 
+        public async Task<int> NextRdNr(int kgnr) {
+            int c = 0;
+            (await WbRde.Where(r => r.KgNr == kgnr).Select(r => r.RdNr).ToListAsync())
+                .ForEach(a => { if (a <= c + 100) c = a; });
+            return c + 1;
+        }
+
         public async Task<WineQualLevel> GetWineQualityLevel(double kmw) {
             return await WineQualityLevels
                 .Where(q => !q.IsPredicate && (q.MinKmw == null || q.MinKmw <= kmw))