Add CMFRT coding standards documentation and examples

- Introduced guidelines for "one codeunit one global function" architecture to enforce single responsibility in AL code.
- Added best practices and anti-patterns for adding parameters via overloads to maintain backward compatibility.
- Documented the importance of never deleting members in AL and always marking them as obsolete.
- Established the requirement for OnBefore and OnAfter integration events for global procedures to enhance extensibility.
- Defined naming conventions for CMFRT objects, including prefixes and object ID ranges to avoid conflicts.
- Implemented patterns for case statements to ensure all cases are handled, including the necessity of an else clause.
- Introduced the interface injection pattern to allow pluggable operations in table-level code.
- Recommended using Confirm Management for user confirmations to improve testability.
- Established a three-permission set pattern for security to ensure proper access control.
- Created a review skill for CMFRT AL standards to automate compliance checks against established guidelines.

custom/knowledge/patterns/cmfrt-case-requires-else.bad.al

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+codeunit 2045760 "CMFRT GD Status Processor"
+{
+    procedure CMFRTGDProcessByStatus(Status: Enum "CMFRT GD POI Status")
+    begin
+        // No else clause — a future enum value silently falls through
+        // with no error and no action, producing a silent no-op.
+        case Status of
+            Status::Active:
+                CMFRTGDActivatePOI();
+            Status::Inactive:
+                CMFRTGDDeactivatePOI();
+            Status::Pending:
+                CMFRTGDQueuePOIForReview();
+        end;
+    end;
+}

custom/knowledge/patterns/cmfrt-case-requires-else.good.al

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+codeunit 2045760 "CMFRT GD Status Processor"
+{
+    procedure CMFRTGDProcessByStatus(Status: Enum "CMFRT GD POI Status")
+    begin
+        case Status of
+            Status::Active:
+                CMFRTGDActivatePOI();
+            Status::Inactive:
+                CMFRTGDDeactivatePOI();
+            Status::Pending:
+                CMFRTGDQueuePOIForReview();
+            else
+                // New enum values added in the future are caught here
+                // instead of silently doing nothing.
+                Error('Unhandled POI status: %1', Status);
+        end;
+    end;
+}

custom/knowledge/patterns/cmfrt-case-requires-else.md

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+---
+bc-version: [all]
+domain: patterns
+keywords: [case, else, defensive-coding, unhandled-case, enum, option, silent-failure]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# CMFRT CASE statement requires ELSE clause
+
+## Description
+
+Every `case` statement in CMFRT AL code must include an `else` clause. The rule is unconditional: even when every currently known value of the matched expression is enumerated, the `else` clause guards against future values being added to an enum, option field, or integer range. Without `else`, a new value passes through the `case` block silently — no error, no action — and the resulting silent no-op or data corruption is difficult to trace because the `case` appears correct at the time it was written.
+
+## Best Practice
+
+Always add an `else` clause to every `case` statement. When no meaningful action applies to unexpected values, the `else` clause should raise an error that identifies the unexpected value, log it, or call a dedicated handler procedure. The key outcome is that the unexpected case is detected at runtime rather than silently ignored.
+
+See sample: `cmfrt-case-requires-else.good.al`.
+
+## Anti Pattern
+
+Writing a `case` statement that enumerates all currently known values and omits `else`. The code appears complete but becomes a silent failure mode the moment a new enum value is added by a future developer or by a base application update, because the added value simply falls through the entire `case` block.
+
+See sample: `cmfrt-case-requires-else.bad.al`.

custom/knowledge/patterns/cmfrt-interface-injection.bad.al

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+// Monolithic entry-point: the implementation is embedded, there is no interface,
+// and there is no OnBefore event. Dependent extensions cannot override the
+// calculation without an AL override hack.
+table 2045090 "CMFRT MS Measure State"
+{
+    procedure CalcTotals()
+    begin
+        // All calculation logic is hard-coded here.
+        Rec."Total Amount" := Rec."Line Amount" + Rec."Tax Amount";
+        Rec.Modify();
+    end;
+}

custom/knowledge/patterns/cmfrt-interface-injection.good.al

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+// Step 1: Interface with a single procedure.
+interface "CMFRT MS ICalcTotals"
+{
+    procedure CMFRTMSCalcTotals(var MeasureState: Record "CMFRT MS Measure State");
+}
+
+// Step 2 & 3: Base-table entry point and interface-accepting overload.
+table 2045090 "CMFRT MS Measure State"
+{
+    procedure CalcTotals()
+    var
+        DefaultImpl: Codeunit "CMFRT MS CalcTotals Impl";
+        Handled: Boolean;
+    begin
+        OnBeforeDefaultImplCalcTotals(Rec, Handled);
+        if Handled then
+            exit;
+        CalcTotals(DefaultImpl);
+    end;
+
+    procedure CalcTotals(CalcImpl: Interface "CMFRT MS ICalcTotals")
+    begin
+        CalcImpl.CMFRTMSCalcTotals(Rec);
+    end;
+
+    // Step 4: OnBefore event with Handled pattern.
+    [IntegrationEvent(false, false)]
+    local procedure OnBeforeDefaultImplCalcTotals(var Ms: Record "CMFRT MS Measure State"; var Handled: Boolean)
+    begin
+    end;
+}

custom/knowledge/patterns/cmfrt-interface-injection.md

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+---
+bc-version: [all]
+domain: patterns
+keywords: [interface, injection, extensibility, implementation, handled, on-before, pluggable, override]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# CMFRT interface injection pattern
+
+## Description
+
+The CMFRT interface injection pattern makes any table-level operation pluggable by dependent extensions using a four-step structure. Step 1: define an AL `interface` with a single procedure matching the operation's signature. Step 2: add a parameterless entry-point procedure on the base table that instantiates the default implementation codeunit, fires an `OnBefore` integration event with `var Handled: Boolean`, exits early if `Handled` is true, and otherwise calls the overloaded form in Step 3. Step 3: add an overloaded procedure on the same table that accepts the interface as a parameter and delegates to it. Step 4: declare the `[IntegrationEvent(false, false)]` `OnBefore` event as a local procedure passing `var Handled: Boolean`. Dependent extensions subscribe to `OnBefore`, set `Handled := true`, and call the overloaded procedure with their own implementation codeunit.
+
+## Best Practice
+
+Apply this pattern whenever a calculation or operation might need different behaviour in different customer deployments. The separation between the parameterless entry-point and the interface-accepting overload means a subscriber can inject an alternative implementation without modifying the base table. The default implementation remains the fallback for all extensions that do not subscribe.
+
+See sample: `cmfrt-interface-injection.good.al`.
+
+## Anti Pattern
+
+Placing the entire implementation directly inside the entry-point procedure with no interface and no `OnBefore` event. Monolithic entry points cannot be overridden by a subscriber without an AL override pattern, which is a breaking change for the overriding extension every time the base procedure is updated.
+
+See sample: `cmfrt-interface-injection.bad.al`.

custom/knowledge/patterns/cmfrt-use-confirmmanagement.bad.al

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+codeunit 2045750 "CMFRT GD Deletion Handler"
+{
+    procedure CMFRTGDDeletePOI(POICode: Code[20])
+    var
+        CMFRTGDPOI: Record "CMFRT GD POI";
+    begin
+        // Confirm built-in blocks test automation — automated tests hang here.
+        if not Confirm('Delete POI %1?', false, POICode) then
+            exit;
+
+        if CMFRTGDPOI.Get(POICode) then
+            CMFRTGDPOI.Delete(true);
+    end;
+}

custom/knowledge/patterns/cmfrt-use-confirmmanagement.good.al

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+codeunit 2045750 "CMFRT GD Deletion Handler"
+{
+    procedure CMFRTGDDeletePOI(POICode: Code[20])
+    var
+        CMFRTGDPOI: Record "CMFRT GD POI";
+        ConfirmManagement: Codeunit "Confirm Management";
+        DeleteConfirmQst: Label 'Delete POI %1?', Comment = '%1 = POI Code';
+    begin
+        if not ConfirmManagement.GetResponseOrDefault(StrSubstNo(DeleteConfirmQst, POICode), false) then
+            exit;
+
+        if CMFRTGDPOI.Get(POICode) then
+            CMFRTGDPOI.Delete(true);
+    end;
+}

custom/knowledge/patterns/cmfrt-use-confirmmanagement.md

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+---
+bc-version: [all]
+domain: patterns
+keywords: [confirm, confirmmanagement, dialog, user-confirmation, test, automation, testability]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# CMFRT use ConfirmManagement instead of Confirm
+
+## Description
+
+CMFRT AL code must use the `"Confirm Management"` codeunit to prompt the user for confirmation instead of calling the `Confirm` built-in function directly. `"Confirm Management"` wraps `Confirm` and resolves confirmation dialogs without displaying UI during automated test runs, making test behaviour deterministic. The `Confirm` built-in always renders a modal dialog regardless of execution context, which causes automated tests to hang waiting for user input.
+
+## Best Practice
+
+Declare `ConfirmManagement: Codeunit "Confirm Management";` as a local variable and call `ConfirmManagement.GetResponseOrDefault(QuestionLbl, true)`. The codeunit suppresses the dialog automatically in test context. Use a `Label` for the question text so it is translatable.
+
+See sample: `cmfrt-use-confirmmanagement.good.al`.
+
+## Anti Pattern
+
+Calling `if Confirm(QuestionText, true) then` directly. Direct `Confirm` calls are not interceptable by the test framework: the modal dialog appears during automated test runs, causing the test to stall indefinitely or fail with a UI-interaction error. Tests that hit a `Confirm` call cannot be run in a CI pipeline without manual intervention.
+
+See sample: `cmfrt-use-confirmmanagement.bad.al`.