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/@npmcli/installed-package-contents/bin/index.js

@@ -0,0 +1,44 @@
+#! /usr/bin/env node
+
+const { relative } = require('path')
+const pkgContents = require('../')
+
+const usage = `Usage:
+  installed-package-contents <path> [-d<n> --depth=<n>]
+
+Lists the files installed for a package specified by <path>.
+
+Options:
+  -d<n> --depth=<n>   Provide a numeric value ("Infinity" is allowed)
+                      to specify how deep in the file tree to traverse.
+                      Default=1
+  -h --help           Show this usage information`
+
+const options = {}
+
+process.argv.slice(2).forEach(arg => {
+  let match
+  if ((match = arg.match(/^(?:--depth=|-d)([0-9]+|Infinity)/))) {
+    options.depth = +match[1]
+  } else if (arg === '-h' || arg === '--help') {
+    console.log(usage)
+    process.exit(0)
+  } else {
+    options.path = arg
+  }
+})
+
+if (!options.path) {
+  console.error('ERROR: no path provided')
+  console.error(usage)
+  process.exit(1)
+}
+
+const cwd = process.cwd()
+
+pkgContents(options)
+  .then(list => list.sort().forEach(p => console.log(relative(cwd, p))))
+  .catch(/* istanbul ignore next - pretty unusual */ er => {
+    console.error(er)
+    process.exit(1)
+  })