Add 18 more community AL/BC patterns across appsource, data-modeling, error-handling, security, style, testing, ui, upgrade, and web-services

Second contribution from CURABIS ApS, generalized from patterns observed across real AppSource/PTE development. Cross-checked against the current microsoft/knowledge corpus before opening; several originally-drafted candidates were dropped as duplicates of existing files.

microsoft/knowledge/error-handling/log-writes-must-survive-rollback.bad.al

@@ -0,0 +1,24 @@
+codeunit 50101 "Sample Web Service Caller"
+{
+    procedure CallExternalService()
+    var
+        ErrorLogEntry: Record "Sample Error Log";
+    begin
+        // BUG: the log write happens inside the same transaction as the
+        // risky call, using the same Record instance as the caller.
+        if not TryCallService() then begin
+            ErrorLogEntry.Init();
+            ErrorLogEntry."Error Message" := CopyStr(GetLastErrorText(), 1, 250);
+            ErrorLogEntry.Insert();
+            Error(GetLastErrorText());
+            // Error() above rolls back this transaction - including the
+            // Insert() just made. The failure is never actually logged.
+        end;
+    end;
+
+    [TryFunction]
+    local procedure TryCallService()
+    begin
+        // ... external call that may fail ...
+    end;
+}