The guide learns the thread it was silent on, and grows a vendor-neutral twin

CLAUDE.md bumps to v14: a new Comments section teaches the comments/ mechanics
(chronology-as-ordering, author vs modified-by, .draft/.trash as the app's,
retract-by-follow-up), and a new "Use the thread: journal your work" section
teaches conduct the guide never had — body is the spec, thread is the journal,
post a plan cold-reader-ready on start, decisions as they're made, questions
as comments, re-read before resuming, close with verification. comments/
leaves the reserved-tracker-keys list; the Layout diagram gains comments/ and
AGENTS.md.

The app now writes a byte-identical twin at AGENTS.md, the vendor-neutral name
most non-Claude tools read — same lifecycle as CLAUDE.md, decided and healed
independently per claimed name, both funneling a markerless foreign file to
the single shared CLAUDE.user.md rescue. AgentGuide.install now returns
[Displacement]; IntegrityRules.claimedRootNames and BoardStore.refreshAgentGuide
cover both names; ChangeNarrator's guide-commit path check widens to both.

DESIGN/08-agent-integration.md amends: the agent-guide section gains the
Comments and Use-the-thread bullets and an AGENTS.md twin paragraph.

Claude-Session: https://claude.ai/code/session_014PtZdPwqZuqEDLc6wZMtEy

Kanban/Changes/ChangeNarrator.swift

@@ -847,10 +847,12 @@ enum ChangeNarrator {
 
             // **N is a pure function of the file's content** (06; the m10 agent-guide card's deferred
             // bullet): the version marker on the guide's first line, read here rather than tagged at
-            // the write site — "the no-interception rule stands". A `CLAUDE.md` with no marker is not
-            // an old guide, it is somebody else's file (`AgentGuide.installedVersion`), and it
-            // composes as the ordinary path it is.
-            if path == AgentGuide.filename,
+            // the write site — "the no-interception rule stands". A guide filename with no marker is
+            // not an old guide, it is somebody else's file (`AgentGuide.installedVersion`), and it
+            // composes as the ordinary path it is. **Both claimed names** (`CLAUDE.md` and its
+            // `AGENTS.md` twin, ruled 2026-08-09) share this shape — the twin carries the identical
+            // marker line by construction, so the same version parse answers for either path.
+            if AgentGuide.targetFilenames.contains(path),
                let version = request.agentGuideText.flatMap(AgentGuide.installedVersion(of:)) {
                 events.append(Event(kind: .agentGuide, subject: "Update agent guide (v\(version))", paths: [path]))
                 continue