feat(v3): restructure project + add complete frontend

- Restructure: move backend from new_project/ to backend/
- Add full React/TypeScript frontend (37 pages, 17 services, 16 type defs, 11 query hooks)
- Add docs/ with SRS specs, user stories, and workflow documentation
- Update .gitignore for new directory layout

Workflows implemented:
  WF1 User Signup, WF2 Placement Test, WF3 Exam Configuration,
  WF4 General English Exam, WF5 Course Generation,
  WF6 Entity Student Onboarding, AI Course Generation,
  Adaptive Learning Engine UI, White-Label Branding, Score Release

Made-with: Cursor

src/components/NavLink.tsx

@@ -0,0 +1,28 @@
+import { NavLink as RouterNavLink, NavLinkProps } from "react-router-dom";
+import { forwardRef } from "react";
+import { cn } from "@/lib/utils";
+
+interface NavLinkCompatProps extends Omit<NavLinkProps, "className"> {
+  className?: string;
+  activeClassName?: string;
+  pendingClassName?: string;
+}
+
+const NavLink = forwardRef<HTMLAnchorElement, NavLinkCompatProps>(
+  ({ className, activeClassName, pendingClassName, to, ...props }, ref) => {
+    return (
+      <RouterNavLink
+        ref={ref}
+        to={to}
+        className={({ isActive, isPending }) =>
+          cn(className, isActive && activeClassName, isPending && pendingClassName)
+        }
+        {...props}
+      />
+    );
+  },
+);
+
+NavLink.displayName = "NavLink";
+
+export { NavLink };