Initial commit

src/PowderCoating.Application/Interfaces/IInAppNotificationService.cs

@@ -0,0 +1,14 @@
+namespace PowderCoating.Application.Interfaces;
+
+public interface IInAppNotificationService
+{
+    // Company-scoped notification — shown to all users of that company
+    Task CreateAsync(int companyId, string title, string message, string notificationType,
+        string? link = null, int? quoteId = null, int? invoiceId = null, int? customerId = null);
+
+    // Platform notification — shown only to SuperAdmins
+    Task CreateForSuperAdminsAsync(string title, string message, string notificationType, string? link = null);
+
+    // Broadcast notification — one record per active company, shown to all tenant users
+    Task CreateForAllCompaniesAsync(string title, string message, string notificationType, string? link = null);
+}