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/Dockerfile

@@ -0,0 +1,41 @@
+FROM node:18-alpine AS build
+WORKDIR /app
+COPY package.json package-lock.json ./
+RUN npm ci
+COPY . .
+ARG VITE_API_BASE_URL=/api
+ARG VITE_APP_NAME=EnCoach
+ENV VITE_API_BASE_URL=$VITE_API_BASE_URL
+ENV VITE_APP_NAME=$VITE_APP_NAME
+RUN npm run build
+
+FROM nginx:stable-alpine
+COPY --from=build /app/dist /usr/share/nginx/html
+COPY <<'NGINX' /etc/nginx/conf.d/default.conf
+server {
+    listen 80;
+    server_name _;
+    root /usr/share/nginx/html;
+    index index.html;
+
+    location /api/ {
+        proxy_pass         http://backend:8069/api/;
+        proxy_set_header   Host              $host;
+        proxy_set_header   X-Real-IP         $remote_addr;
+        proxy_set_header   X-Forwarded-For   $proxy_add_x_forwarded_for;
+        proxy_set_header   X-Forwarded-Proto $scheme;
+        proxy_read_timeout 300s;
+    }
+
+    location / {
+        try_files $uri $uri/ /index.html;
+    }
+
+    location ~* \.(?:css|js|svg|png|jpg|jpeg|gif|ico|woff2?|ttf|eot)$ {
+        expires 30d;
+        add_header Cache-Control "public, immutable";
+    }
+}
+NGINX
+EXPOSE 80
+CMD ["nginx", "-g", "daemon off;"]