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/regex-parser/lib/index.js

@@ -0,0 +1,34 @@
+"use strict";
+
+/**
+ * RegexParser
+ * Parses a string input.
+ *
+ * @name RegexParser
+ * @function
+ * @param {String} input The string input that should be parsed as regular
+ * expression.
+ * @return {RegExp} The parsed regular expression.
+ */
+var RegexParser = module.exports = function (input) {
+    // Validate input
+    if (typeof input !== "string") {
+        throw new Error("Invalid input. Input must be a string");
+    }
+
+    // Parse input
+    var m = input.match(/(\/?)(.+)\1([a-z]*)/i);
+
+    // If there's no match, throw an error
+    if (!m) {
+        throw new Error("Invalid regular expression format.");
+    }
+
+    // Filter valid flags: 'g', 'i', 'm', 's', 'u', and 'y'
+    var validFlags = Array.from(new Set(m[3])).filter(function (flag) {
+        return "gimsuy".includes(flag);
+    }).join("");
+
+    // Create the regular expression
+    return new RegExp(m[2], validFlags);
+};