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

frontend/src/components/ui/textarea.tsx

@@ -0,0 +1,21 @@
+import * as React from "react";
+
+import { cn } from "@/lib/utils";
+
+export interface TextareaProps extends React.TextareaHTMLAttributes<HTMLTextAreaElement> {}
+
+const Textarea = React.forwardRef<HTMLTextAreaElement, TextareaProps>(({ className, ...props }, ref) => {
+  return (
+    <textarea
+      className={cn(
+        "flex min-h-[80px] w-full rounded-md border border-input bg-background px-3 py-2 text-sm ring-offset-background placeholder:text-muted-foreground focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-offset-2 disabled:cursor-not-allowed disabled:opacity-50",
+        className,
+      )}
+      ref={ref}
+      {...props}
+    />
+  );
+});
+Textarea.displayName = "Textarea";
+
+export { Textarea };