Extract 55 knowledge articles from BC review-agent prompt

Adds 55 articles (plus 76 code samples) spanning four new domains and
two existing domains, extracted from the internal Business Central
review-agent prompt. Content was filtered against BCQuality's
remedial-knowledge premise: each article encodes BC-specific behaviour,
a CodeCop rule, a platform API semantic, or an anti-false-positive
guideline that a capable LLM would otherwise get wrong.

New domains:
- privacy (11 articles): DataClassification inheritance semantics, the
  StrSubstNo-defeats-Error-telemetry-classification pitfall, Privacy
  Notice consent for outgoing requests, anti-false-positives for pages
  and in-memory data.
- upgrade (11 articles): upgrade-codeunit structure, upgrade-tag
  lifecycle and registration, protected DB reads, DataTransfer for
  large datasets, InitValue semantics, enum-ordinal preservation,
  obsolete-workflow, first-install detection.
- ui (9 articles): caption capitalization by phrase type, tooltip voice,
  teaching-tip vs tooltip, tour-tip conventions, character limits,
  banned terms, ampersand handling, title punctuation.
- style (11 articles): label-suffix convention, API page naming,
  temporary-variable prefix, label properties (Comment/Locked), named
  invocations, FieldCaption in user messages, OptionCaption pairing,
  Error-parameter passing, `this` keyword, required parentheses, file
  naming.

Gaps in existing domains:
- performance (11 articles): production-scale table catalog (no row
  counts, per internal-data concern), anti-false-positive for bounded
  tables, guard-before-Get ordering, redundant-Get-in-OnAfterGetRecord,
  LockTable in read-only helpers, combined ModifyAll passes, writes in
  OnAfterGetRecord, SetLoadFields heuristics, temporary-table
  regressions, FlowField source-table widening, MaintainSQLIndex
  disabling SIFT.
- security (2 articles): environment-specific hardcoded GUIDs,
  ValidateTableRelation=false on user input.

Intentionally excluded: specific production P95 row-count numbers
(aggregated internal telemetry); rewritten as categorical guidance on
which tables to treat as production-scale without publishing sizes.

All articles use `bc-version: [all]` (applies to every BC version, per
the new schema sentinel). Validator passes with 0 errors / 0 warnings.

microsoft/knowledge/performance/do-not-modify-records-in-onaftergetrecord.good.al

@@ -0,0 +1,35 @@
+page 51208 "Perf Sample NoModifyOAGR Good"
+{
+    PageType = List;
+    SourceTable = Customer;
+
+    layout
+    {
+        area(Content)
+        {
+            repeater(Group)
+            {
+                field("No."; Rec."No.") { ApplicationArea = All; }
+                field(WarningFlag; ShowWarning)
+                {
+                    ApplicationArea = All;
+                    Caption = 'Warning';
+                }
+            }
+        }
+    }
+
+    trigger OnAfterGetRecord()
+    begin
+        // Page-local variable. No database write per row.
+        ShowWarning := CalcWarning(Rec);
+    end;
+
+    var
+        ShowWarning: Boolean;
+
+    local procedure CalcWarning(var Customer: Record Customer): Boolean
+    begin
+        exit(false);
+    end;
+}