Add new action skills for AL testing and documentation

- Introduced `al-test-writer` to generate AL test codeunits for production objects based on TDD principles.
- Added `al-userguide-test-writer` to create test codeunits from user guide steps, mapping actions and assertions.
- Implemented `bc-extension-test-guide` to generate a comprehensive TEST_GUIDE.md for Business Central extensions, covering various categories.
- Created `bc-webclient-runner` to automate UI testing of the Business Central web client, capturing screenshots and asserting UI states.
- Developed `page-scripting-e2e` to produce a recording plan for Page Scripting, ensuring a structured approach to browser-level testing.

custom/knowledge/integration/version-business-events-and-keep-payloads-stable.bad.al

@@ -0,0 +1,30 @@
+// Anti-pattern: mutating a published signature, passing the whole record plus a secret, and
+// firing without validation or failure classification. Every external subscriber breaks, and
+// credentials and every table field leak into the payload.
+
+codeunit 50173 "Order Events Bad"
+{
+    // This event already shipped as OnOrderConfirmed(OrderNo: Code[20]). Subscribers bound to
+    // that signature. Editing it IN PLACE to add parameters silently breaks all of them: there
+    // is no compiler across the boundary, so the notification just starts arriving in the wrong
+    // shape and processing fails on the far side, far from this change.
+    [ExternalBusinessEvent('OrderConfirmed', 'Order confirmed', 'Raised on confirm', EventCategory::Sales)]
+    procedure OnOrderConfirmed(var SalesHeader: Record "Sales Header"; ApiKey: Text)
+    // BAD: the full record exposes every field of Sales Header to every subscriber and couples
+    // the contract to the table layout. ApiKey leaks a secret credential into the payload.
+    begin
+    end;
+}
+
+codeunit 50174 "Order Publisher Bad"
+{
+    procedure Publish(SalesHeader: Record "Sales Header")
+    var
+        Events: Codeunit "Order Events Bad";
+    begin
+        // BAD: no validation. A header with no document number is published and then, because
+        // the data is permanently invalid, retried by the platform indefinitely. There is no
+        // transient/permanent classification, so an unfixable payload is treated like a blip.
+        Events.OnOrderConfirmed(SalesHeader, GetSecretApiKey());
+    end;
+}