Seed community performance and security knowledge

Ports 14 concern-sized articles (8 performance, 6 security) and 25
AL samples from BC Code Intelligence, restructured to BCQuality's v1
schema and layered under /community/knowledge/. Each article is
atomic, under 100 lines, and ships <slug>.good.al and (where the
pattern has a clear anti-example) <slug>.bad.al siblings.

Jesper's microsoft-layer leaves (al-performance-review and
al-security-review) source across every enabled layer via
*/knowledge/<domain>/**, so these additions are picked up by the
existing action skills without any new skill definitions.

Performance (8):
  - use-deleteall-for-filtered-bulk-deletion
  - call-setloadfields-before-filters
  - load-common-fields-before-branching-on-case
  - load-only-primary-key-fields-for-reference-work
  - omit-filter-only-fields-from-setloadfields
  - choose-maintainsiftindex-by-read-write-ratio
  - avoid-growing-globals-in-singleinstance-subscribers
  - order-case-branches-by-frequency

Security (6):
  - classify-every-field-with-dataclassification
  - protect-sensitive-data-in-temporary-tables
  - guard-bulk-operations-with-istemporary
  - compose-permission-sets-with-included-sets
  - do-not-grant-rights-beyond-a-users-entitlement
  - prefer-oauth2-over-api-keys-for-external-http-calls

Graveyard-bound items (not ported; to be captured in a later
/docs/triage-graveyard.md):
  - testfield-performance (soft guidance, low actionability)
  - table-event-batch-operation-impact (keep-event-subscribers-lightweight
    already carries the core insight)
  - Most of /roger-reviewer (AL formatting - frontier-model territory)
  - sift-technology-fundamentals (descriptive, not a citable concern)
  - bc-telemetry-buddy-* (tooling promotion, not guidance)

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

community/knowledge/security/prefer-oauth2-over-api-keys-for-external-http-calls.good.al

@@ -0,0 +1,44 @@
+codeunit 50100 "Partner API Client"
+{
+    procedure FetchOrders(var Response: Text): Boolean
+    var
+        OAuth2: Codeunit OAuth2;
+        HttpClient: HttpClient;
+        HttpRequest: HttpRequestMessage;
+        HttpResponse: HttpResponseMessage;
+        AccessToken: SecretText;
+        Scopes: List of [Text];
+    begin
+        Scopes.Add('https://partner.example.com/.default');
+
+        // Client-credentials flow for service-to-service. Tokens expire and rotate
+        // on their own schedule; secret and client id are retrieved from IsolatedStorage.
+        if not OAuth2.AcquireTokenWithClientCredentials(
+                 GetClientIdFromIsolatedStorage(),
+                 GetClientSecretFromIsolatedStorage(),
+                 'https://login.example.com/tenantid/oauth2/v2.0/token',
+                 '',
+                 Scopes,
+                 AccessToken)
+        then
+            exit(false);
+
+        HttpRequest.SetRequestUri('https://partner.example.com/orders');
+        HttpRequest.Method('GET');
+        HttpRequest.GetHeaders().Add('Authorization', SecretStrSubstNo('Bearer %1', AccessToken));
+
+        if not HttpClient.Send(HttpRequest, HttpResponse) then
+            exit(false);
+
+        HttpResponse.Content.ReadAs(Response);
+        exit(HttpResponse.IsSuccessStatusCode);
+    end;
+
+    local procedure GetClientIdFromIsolatedStorage(): Text
+    begin
+    end;
+
+    local procedure GetClientSecretFromIsolatedStorage(): SecretText
+    begin
+    end;
+}