Initial commit: notification-elements-demo app

Interactive Angular 19 demo for @sda/notification-elements-ui with
6 sections: Bell & Feed, Notification Center, Inbox, Comments &
Threads, Mention Input, and Full-Featured layout. Includes mock
data, dark mode toggle, and real-time event log.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

node_modules/pacote/lib/util/npm.js

@@ -0,0 +1,14 @@
+// run an npm command
+const spawn = require('@npmcli/promise-spawn')
+
+module.exports = (npmBin, npmCommand, cwd, env, extra) => {
+  const isJS = npmBin.endsWith('.js')
+  const cmd = isJS ? process.execPath : npmBin
+  const args = (isJS ? [npmBin] : []).concat(npmCommand)
+  // when installing to run the `prepare` script for a git dep, we need
+  // to ensure that we don't run into a cycle of checking out packages
+  // in temp directories.  this lets us link previously-seen repos that
+  // are also being prepared.
+
+  return spawn(cmd, args, { cwd, env }, extra)
+}