Add Job Queue reliability and scheduling guidance (#148)

* knowledge(performance): add job queue reliability guidance

* Address Job Queue review feedback

* Address Job Queue routing review feedback

* Encode job queue conflict in fixtures

microsoft/knowledge/performance/job-queue-external-effects-must-be-idempotent.good.al

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+table 50112 "Queued Export Good"
+{
+    DataClassification = CustomerContent;
+
+    fields
+    {
+        field(1; "Entry No."; Integer)
+        {
+            AutoIncrement = true;
+        }
+        field(2; Payload; Text[250])
+        {
+        }
+    }
+
+    keys
+    {
+        key(PK; "Entry No.")
+        {
+            Clustered = true;
+        }
+    }
+
+}
+
+codeunit 50112 "Queued Export Worker Good"
+{
+    TableNo = "Job Queue Entry";
+
+    trigger OnRun()
+    var
+        QueuedExport: Record "Queued Export Good";
+        Client: HttpClient;
+        Content: HttpContent;
+        ContentHeaders: HttpHeaders;
+        JsonPayload: JsonObject;
+        RequestBody: Text;
+        Response: HttpResponseMessage;
+    begin
+        if not QueuedExport.FindFirst() then
+            exit;
+
+        JsonPayload.Add('idempotencyKey', Format(QueuedExport.SystemId));
+        JsonPayload.Add('payload', QueuedExport.Payload);
+        JsonPayload.WriteTo(RequestBody);
+
+        Content.WriteFrom(RequestBody);
+        Content.GetHeaders(ContentHeaders);
+        ContentHeaders.Clear();
+        ContentHeaders.Add('Content-Type', 'application/json');
+        Client.Post('https://example.local/exports', Content, Response);
+        if not Response.IsSuccessStatusCode() then
+            Error('Export failed with HTTP status %1.', Response.HttpStatusCode());
+
+        // The external service must atomically create a record only when idempotencyKey
+        // does not exist. When the key already exists, it must return the existing record
+        // without repeating the side effect.
+        UpdateLocalStatus();
+        QueuedExport.Delete();
+    end;
+
+    local procedure UpdateLocalStatus()
+    begin
+    end;
+}