Add 'Modified' tracking for Prospect entity

Introduce a 'Modified' field to track the last modification date of prospects. Automatically update this field on changes and integrate it in UI display for better transparency.

FoodsharingSiegen.Server/Data/Service/ProspectService.cs

@@ -44,6 +44,7 @@ namespace FoodsharingSiegen.Server.Data.Service
                 interaction.Created = DateTime.UtcNow;
 
                 targetProspect.Interactions.Add(interaction);
+                targetProspect.Modified = DateTime.UtcNow;
                 
                 await Context.SaveChangesAsync();
                 
@@ -77,6 +78,7 @@ namespace FoodsharingSiegen.Server.Data.Service
                 if (prospect == null) return new(new Exception("Cannot be empty"));
 
                 prospect.Created = DateTime.UtcNow;
+                prospect.Modified = DateTime.UtcNow;
                 prospect.Id = Guid.Empty;
 
                 await Context.Prospects!.AddAsync(prospect);
@@ -142,8 +144,19 @@ namespace FoodsharingSiegen.Server.Data.Service
         {
             try
             {
-                Context.Interactions!.Remove(new() { Id = interactionId });
+                var interaction = await Context.Interactions!.AsNoTracking().FirstOrDefaultAsync(x => x.Id == interactionId);
+                if(interaction == null) return new(new Exception("Interaction not found"));
+                
+                Context.Interactions!.Remove(new() { Id = interaction.Id });
                 await Context.SaveChangesAsync();
+                
+                // Update prospect modified date
+                var prospect = await Context.Prospects!.FirstOrDefaultAsync(x => x.Id == interaction.ProspectID);
+                if (prospect != null)
+                {
+                    prospect.Modified = DateTime.UtcNow;
+                    await Context.SaveChangesAsync();
+                }
 
                 await AuditService.Insert(AuditType.RemoveInteraction, "?");
                 
@@ -176,6 +189,7 @@ namespace FoodsharingSiegen.Server.Data.Service
                 entityProspect.FsId = prospect.FsId;
                 entityProspect.Warning = prospect.Warning;
                 entityProspect.RecordState = prospect.RecordState;
+                entityProspect.Modified = DateTime.UtcNow;
             
                 var saveR = await Context.SaveChangesAsync();