feat(fleet): seed role registry markdown library (#655)

packages/mosaic/framework/install.sh

@@ -25,7 +25,9 @@ INSTALL_MODE="${MOSAIC_INSTALL_MODE:-prompt}"
 # User-created content in these paths survives rsync --delete.
 #
 # fleet/* — the framework SEEDS only fleet/examples, fleet/roles, and
-# fleet/roster.schema.json (synced normally). The user's own fleet files MUST
+# fleet/roster.schema.json (synced normally — every fleet/roles/*.md role contract
+# lands automatically via this sync, so no per-file entry is needed). The user's
+# own fleet files MUST
 # survive `mosaic update` (which runs this sync automatically): the active
 # roster (`fleet/roster.yaml` + any other `fleet/*.yaml`), per-agent env
 # (`fleet/agents/`), and heartbeat run dir (`fleet/run/`). Without these, an