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/hooks/queries/useExamSession.ts

@@ -0,0 +1,34 @@
+import { useQuery, useMutation } from "@tanstack/react-query";
+import { queryKeys } from "./keys";
+import { examSessionService } from "@/services/exam-session.service";
+import type { ExamAutoSave } from "@/types";
+
+export function useExamSession(examId: number) {
+  return useQuery({
+    queryKey: queryKeys.examSession.session(examId),
+    queryFn: () => examSessionService.getSession(examId),
+    enabled: !!examId,
+  });
+}
+
+export function useExamStatus(examId: number, enabled: boolean) {
+  return useQuery({
+    queryKey: queryKeys.examSession.status(examId),
+    queryFn: () => examSessionService.getStatus(examId),
+    enabled: !!examId && enabled,
+    refetchInterval: 10000,
+  });
+}
+
+export function useExamAutoSave() {
+  return useMutation({
+    mutationFn: (data: { examId: number; payload: ExamAutoSave }) =>
+      examSessionService.autoSave(data.examId, data.payload),
+  });
+}
+
+export function useExamSubmit() {
+  return useMutation({
+    mutationFn: (examId: number) => examSessionService.submit(examId),
+  });
+}