feat(community/agents): add AL agent quality guidance

- add 20 agent knowledge rules with good and bad AL samples
- clarify setup dialog shape, temporary persistence, permissions, profiles, instructions, capability registration, and interface wiring
- add the community-owned AL agents review skill
- make review fixture discovery layer-aware with custom, community, and Microsoft precedence
- document layer-aware evaluation behavior

community/knowledge/agents/cross-app-agent-calls-need-your-public-api.good.al

@@ -0,0 +1,21 @@
+codeunit 50110 "Sales Review Agent API"
+{
+    Access = Public;
+
+    procedure SetDisplayName(AgentUserSecurityId: Guid; NewDisplayName: Text[80])
+    var
+        Agent: Codeunit Agent;
+    begin
+        Agent.SetDisplayName(AgentUserSecurityId, NewDisplayName);
+    end;
+
+    procedure SetActiveState(AgentUserSecurityId: Guid; ActivateAgent: Boolean)
+    var
+        Agent: Codeunit Agent;
+    begin
+        if ActivateAgent then
+            Agent.Activate(AgentUserSecurityId)
+        else
+            Agent.Deactivate(AgentUserSecurityId);
+    end;
+}