Add events knowledge files for integration event patterns

community/knowledge/events/integration-event-parameter-is-a-breaking-change.bad.al

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+// Demonstration only. Shows the wrong way: adding a parameter directly to an existing integration event.
+
+codeunit 50112 "Sales Post Events Bad"
+{
+    // BAD: ShipmentNo added directly to the existing event signature after subscribers already existed.
+    [IntegrationEvent(false, false)]
+    procedure OnAfterPostSalesOrder(var SalesHeader: Record "Sales Header"; ShipmentNo: Code[20])
+    begin
+    end;
+
+    procedure PostSalesOrder(var SalesHeader: Record "Sales Header"; ShipmentNo: Code[20])
+    begin
+        // ... posting logic ...
+        OnAfterPostSalesOrder(SalesHeader, ShipmentNo);
+    end;
+}
+
+codeunit 50113 "Existing Subscriber Bad"
+{
+    // COMPILE ERROR (AL0306): subscriber signature no longer matches the publisher.
+    // "The event subscriber method signature does not match the event publisher method signature."
+    // ShipmentNo was not on the original event. Every extension that subscribed breaks immediately -
+    // no deprecation period, no warning, no grace. The parameter change is a breaking change.
+    [EventSubscriber(ObjectType::Codeunit, Codeunit::"Sales Post Events Bad", 'OnAfterPostSalesOrder', '', false, false)]
+    local procedure HandleAfterPostSalesOrder(var SalesHeader: Record "Sales Header")
+    begin
+        // This procedure no longer compiles after ShipmentNo was added to the publisher.
+    end;
+}