fix: only catalog hosts are jump targets (v1.19.0)

isManagedHost() treated a missing metadata.managed flag as permission, so
any host the SSO merely discovered -- an unpromoted Proxmox guest, a UniFi
client -- was offered in the TUI picker and accepted by the username
grammar.

Replaced with isCatalogHost(), mirroring the rule the SSO Directory's own
listing applies: a resource carrying discovery_sources but never promoted
is excluded; hand-created hosts and promoted ones are included; an
explicit managed:false is always excluded.

The two copies of this rule have now drifted apart once. If a third
consumer needs it, hoist it into @simpleworkjs/directory-schema rather
than copying again.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

nodejs/package.json

@@ -1,6 +1,6 @@
 {
   "name": "t42-jump-host",
-  "version": "1.18.0",
+  "version": "1.19.0",
   "description": "SSH jump host for the theta42 stack — LDAP-authenticated, directory-driven host bridging with audit and metrics",
   "author": [
     {