Adopt @simpleworkjs/frontend's messages/modal/validate modules

Same swap as sso-manager-node/proxy: vendored app.util.actionMessage/
actionConfirm replaced by @simpleworkjs/frontend's app.messages.action/
confirm; vendored val.js replaced by the package's app.validate.js.
jump-host's views don't call actionMessage/actionConfirm/alert directly,
so no view changes are needed beyond the script includes.

app.api/app.auth/app.pubsub/app.socket in app-base.js are untouched, same
reasoning as the other two apps' PRs.

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

nodejs/routes/render.js

@@ -21,7 +21,7 @@ const values = {
 // as the sibling apps), and the app's own JS/CSS/img from public/.
 mountStaticModules(router, {
 	root: path.join(__dirname, '..'),
-	deps: ['bootstrap', 'mustache', 'jquery', '@fortawesome', 'moment', 'jq-repeat'],
+	deps: ['bootstrap', 'mustache', 'jquery', '@fortawesome', 'moment', 'jq-repeat', '@simpleworkjs/frontend'],
 });
 
 // Liveness probe — no auth.