Say on every directory how it treats files it does not know, and check it (issue 1024, ADR 0422)

Every directory and archive resource carries `unknown`: move-out for a home folder whose program writes nothing there (the node-engine, delivered in mesh-host #117, moves the rest to ~/.local/state/mesh-moved/<module>/ with a list), module for ~/.ssh and ~/.claude, program elsewhere; `knows` keeps what a program or the operator relies on (powerlevel10k's compiled files, i3's scripts and the asus/g14 drop-ins, dunst's slack rule, betterbird's records, node-env's forge credential, issue 1033). Two shared folders are no longer declared. Each module's README says it. checks/owned holds every manifest to it; checks/sshdir stays while main's merge check runs it (issue 1035). Tests that pin a manifest follow the new key only. Reviewed in three rounds.

modules/lemurs/README.md

@@ -109,3 +109,10 @@ merges the X resources before any long-lived client connects. On the first login
 the server reset twice within four seconds: the X log showed three server generations. xterm fell
 back to the bitmap `fixed` font, without the mesh's face and colours. lemurs reads its configuration
 when it starts, so the change applies after the next boot.
+
+## Files it does not know
+
+Each directory or archive this module declares says how it treats a file it did not write (ADR 0422, ADR 0416).
+
+- `/etc/lemurs/xsessions`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).
+- `/etc/lemurs/wayland-sessions`: everything in it is the program's; the mesh moves nothing out (ADR 0422 §2).

modules/lemurs/module.json

@@ -43,13 +43,15 @@
       "id": "xsessions",
       "type": "directory",
       "path": "/etc/lemurs/xsessions",
-      "mode": "0755"
+      "mode": "0755",
+      "unknown": "program"
     },
     {
       "id": "wayland-sessions",
       "type": "directory",
       "path": "/etc/lemurs/wayland-sessions",
-      "mode": "0755"
+      "mode": "0755",
+      "unknown": "program"
     },
     {
       "id": "service",