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/media.service.ts

@@ -0,0 +1,15 @@
+import { api } from "@/lib/api-client";
+
+export const mediaService = {
+  async generateListeningAudio(data: { text: string; voice_id?: string }): Promise<{ audio_url: string }> {
+    return api.post("/exam/listening/media", data);
+  },
+
+  async generateSpeakingVideo(data: { text: string; avatar_id?: number }): Promise<{ video_url: string; job_id: string }> {
+    return api.post("/exam/speaking/media", data);
+  },
+
+  async getAvatars(): Promise<{ id: number; name: string; thumbnail: string; voice: string }[]> {
+    return api.get("/exam/avatars");
+  },
+};