knowledge(performance): add community rules for JIT, locks, and false positives

These articles capture BC-specific mechanics agents still invert: partial-record JIT on writes, Reset clearing SetLoadFields, HttpClient inside write transactions, and batched number series, plus negative guidance that stops over-eager Query and IsEmpty "fixes".

Co-authored-by: Cursor <cursoragent@cursor.com>

community/knowledge/performance/query-results-bypass-primary-key-cache.bad.al

@@ -0,0 +1,28 @@
+query 50100 "Query Bypass PK Cache Bad Q"
+{
+    QueryType = Normal;
+
+    elements
+    {
+        dataitem(Customer; Customer)
+        {
+            filter(NoFilter; "No.") { }
+            column(Name; Name) { }
+        }
+    }
+}
+
+codeunit 50100 "Query Bypass PK Cache Bad"
+{
+    procedure CustomerName(CustomerNo: Code[20]): Text
+    var
+        CustomerByNo: Query "Query Bypass PK Cache Bad Q";
+    begin
+        // Query Open/Read never hits the server PK cache.
+        CustomerByNo.SetRange(NoFilter, CustomerNo);
+        CustomerByNo.Open();
+        if CustomerByNo.Read() then
+            exit(CustomerByNo.Name);
+        CustomerByNo.Close();
+    end;
+}