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

Same swap as sso-manager-node/jump-host: vendored app.util.actionMessage/
actionConfirm replaced by @simpleworkjs/frontend's app.messages.action/
confirm (real HTML-escaping, toast fallback); vendored val.js replaced by
the package's app.validate.js.

proxy's host/target/hostname validation rules (mirrored from the backend's
utils/hostname_validate.js — wildcard DNS patterns, not something other
apps need) move to public/js/app.js, registered via $.validateSettings,
since they're proxy-specific and don't belong in the shared package's
generic rule set (eq/user/password/ip).

app.api/app.auth/app.pubsub/app.socket in app-base.js are untouched, same
reasoning as sso-manager-node's PR.

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

nodejs/routes/render.js

@@ -23,7 +23,7 @@ const values ={
 // every deploy and isn't cache-busted/fingerprinted.
 mountStaticModules(router, {
   root: path.join(__dirname, '..'),
-  deps: ['bootstrap', 'mustache', 'jquery', '@fortawesome', 'moment', '@popper', 'jq-repeat'],
+  deps: ['bootstrap', 'mustache', 'jquery', '@fortawesome', 'moment', '@popper', 'jq-repeat', '@simpleworkjs/frontend'],
 });
 
 router.get('/', (req, res) => {