feat(auth): implement user authentication system

backend/node_modules/regexpu-core/rewrite-pattern.d.ts

@@ -0,0 +1,17 @@
+declare module "regexpu-core" {
+  export type RegexpuOptions = {
+    unicodeFlag?: "transform" | false;
+    unicodeSetsFlag?: "transform" | false;
+    dotAllFlag?: "transform" | false;
+    unicodePropertyEscapes?: "transform" | false;
+    namedGroups?: "transform" | false;
+    onNamedGroup?: (name: string, index: number) => void;
+    modifiers?: "transform" | false | "parse";
+    onNewFlags?: (flags: string) => void;
+  };
+  export default function rewritePattern(
+    pattern: string,
+    flags: string,
+    options: RegexpuOptions | undefined
+  ): string;
+}