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/services/classrooms.service.ts

@@ -0,0 +1,36 @@
+import { api } from "@/lib/api-client";
+import type { Classroom, ClassroomCreateRequest, PaginatedResponse, PaginationParams, ApiSuccessResponse } from "@/types";
+
+export interface ClassroomListParams extends PaginationParams {
+  entity_id?: number;
+}
+
+export const classroomsService = {
+  async list(params?: ClassroomListParams): Promise<PaginatedResponse<Classroom>> {
+    return api.get<PaginatedResponse<Classroom>>("/groups", params as Record<string, string | number | boolean | undefined>);
+  },
+
+  async getById(id: number): Promise<Classroom> {
+    return api.get<Classroom>(`/groups/${id}`);
+  },
+
+  async create(data: ClassroomCreateRequest): Promise<Classroom> {
+    return api.post<Classroom>("/groups", data);
+  },
+
+  async delete(id: number): Promise<ApiSuccessResponse> {
+    return api.delete<ApiSuccessResponse>(`/groups/${id}`);
+  },
+
+  async transfer(data: { student_ids: number[]; from_id: number; to_id: number }): Promise<ApiSuccessResponse> {
+    return api.post<ApiSuccessResponse>("/groups/transfer", data);
+  },
+
+  async addMembers(id: number, userIds: number[]): Promise<ApiSuccessResponse> {
+    return api.post<ApiSuccessResponse>(`/groups/${id}/members`, { user_ids: userIds });
+  },
+
+  async removeMembers(id: number, userIds: number[]): Promise<ApiSuccessResponse> {
+    return api.post<ApiSuccessResponse>(`/groups/${id}/members/remove`, { user_ids: userIds });
+  },
+};