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/reset-clears-partial-record-selection.good.al

@@ -0,0 +1,15 @@
+codeunit 50100 "Reset Clears LoadFields Good"
+{
+    procedure ListUsCustomerNames()
+    var
+        Customer: Record Customer;
+    begin
+        Customer.Reset();
+        Customer.SetLoadFields(Name);
+        Customer.SetRange("Country/Region Code", 'US');
+        if Customer.FindSet() then
+            repeat
+                Message(Customer.Name);
+            until Customer.Next() = 0;
+    end;
+}