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/services/grading.service.ts

@@ -0,0 +1,26 @@
+import { api } from "@/lib/api-client";
+import type {
+  GradingQueueItem,
+  StudentResponse,
+  RubricCriteria,
+  AIGradeSuggestion,
+  GradeSubmission,
+} from "@/types";
+import type { ApiSuccessResponse } from "@/types";
+
+export const gradingService = {
+  getQueue: (params?: { skill?: string; status?: string; exam_id?: number }) =>
+    api.get<GradingQueueItem[]>("/grading/queue", params as Record<string, string | number | boolean | undefined>),
+
+  getStudentResponse: (attemptId: number, skill: string) =>
+    api.get<StudentResponse>(`/grading/${attemptId}/response`, { skill }),
+
+  getRubric: (attemptId: number, skill: string) =>
+    api.get<RubricCriteria[]>(`/grading/${attemptId}/rubric`, { skill }),
+
+  getAISuggestion: (attemptId: number, skill: string) =>
+    api.post<AIGradeSuggestion>("/grading/ai-suggest", { attempt_id: attemptId, skill }),
+
+  submitGrade: (data: GradeSubmission) =>
+    api.post<ApiSuccessResponse>(`/grading/${data.attempt_id}/submit`, data),
+};