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/analyze-message-error-stops-warning-forces-review.md

@@ -0,0 +1,26 @@
+---
+bc-version: [27..]
+domain: agents
+keywords: [analyzeagenttaskmessage, agent-annotation, error, warning, setrequiresreview]
+technologies: [al]
+countries: [w1]
+application-area: [all]
+---
+
+# AnalyzeAgentTaskMessage: Error stops the task; Warning still requires review
+
+## Description
+
+`IAgentTaskExecution.AnalyzeAgentTaskMessage` runs on inbound and outbound messages. An Error annotation stops processing. A Warning annotation requests user intervention. If analysis returns Warning, the platform still requires approval even when the incoming message used `SetRequiresReview(false)`. Output text can be rewritten here (signature, redaction).
+
+## Best Practice
+
+Validate inbound payloads in analysis: Error when the task must not run; Warning when a human must confirm. For outbound messages, adjust text in this method rather than in a later subscriber. Do not rely on skip-review to bypass warnings.
+
+See sample: `analyze-message-error-stops-warning-forces-review.good.al`.
+
+## Anti Pattern
+
+Ignoring analysis entirely, or emitting Warning while documenting that `SetRequiresReview(false)` means unattended run. Detection signal: empty `AnalyzeAgentTaskMessage` plus skip-review on external input.
+
+See sample: `analyze-message-error-stops-warning-forces-review.bad.al`.