Add community guidance and review support for Business Central agents (#137)

* 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

* fix(community/agents): align setup and permission samples

- mark agent setup pages as non-extensible where required
- narrow the agent profile by hiding an unrelated sales-order field
- define a dedicated read-only permission set for the sales review agent
- assign AL-defined permission sets with system scope and the owning app ID
- clarify the permission scope guidance for default access controls

* Address agent review feedback

community/knowledge/agents/instructions-describe-work-not-tool-ids.md

@@ -0,0 +1,30 @@
+---
+bc-version: [27..]
+domain: agents
+keywords: [instructions, tools, invoke-action, memorize, page-actions]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# Instructions describe outcomes, not page action or tool names
+
+## Description
+
+Agent tools are the UI the profile exposes. Action names and tool ids change across pages and versions. Best-practice guidance is to say what to accomplish, not which tool to invoke. Page state is also not fully in history; values needed later must be memorized. Models paste Promoted action names into the prompt.
+
+## Best Practice
+
+Write steps as business outcomes (release the order, set the hold reason). Tell the agent to memorize identifiers it must reuse. Do not hard-code action captions or tool ids.
+
+See sample: `instructions-describe-work-not-tool-ids.good.al`.
+
+## Anti Pattern
+
+Instructions that say invoke SalesOrder.Post_Promoted or use tool page-42-action-3. Detection signal: instruction text containing Promoted action names or tool identifiers.
+
+See sample: `instructions-describe-work-not-tool-ids.bad.al`.
+
+## See also
+
+`instruction-structure-is-role-rules-steps.md` defines the containing document structure, and `use-documented-instruction-keywords.md` identifies runtime-recognized phrases.