docs: add Cloudflare tunnel setup guide and ports reference

Add step-by-step Cloudflare tunnel setup to README.md with Summit Dental Care as a multi-office example. Create docs/ports.md documenting all service hosts and ports.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docs/ports.md

@@ -0,0 +1,84 @@
+# Development Hosts & Ports
+
+This document defines the default **host** and **port** used by each app/service
+in this turborepo.  
+Update this file whenever a new service is added or port is changed.
+
+---
+
+## Frontend (React + Vite)
+- **Host:** `localhost` (default)  
+  - Use `0.0.0.0` if you need LAN access (phone/other device on same Wi-Fi).  
+- **Port:** `3000`  
+- **Access URLs:**
+  - Local: [http://localhost:3000](http://localhost:3000)
+  - LAN: `http://<your-ip>:3000` (only if HOST=0.0.0.0)
+
+**Current setup:**  
+Frontend is running on `0.0.0.0` and is accessible via the device IP.
+
+**`.env` file:**
+```env
+NODE_ENV=development
+HOST=0.0.0.0
+PORT=3000
+VITE_API_BASE_URL_BACKEND=http://192.168.1.8:5000
+```
+
+`VITE_API_BASE_URL_BACKEND` must point to the backend's IP/port as seen from the browser.  
+Use `localhost` if only accessing from the same machine, or the machine's LAN IP for access from other devices.
+
+---
+
+## Backend (Express.js)
+- **Host:** `0.0.0.0` (all interfaces)
+- **Port:** `5000`  
+- **Access URL:** [http://localhost:5000](http://localhost:5000)
+
+**Current setup:**  
+Runs on all interfaces and allows configured frontend URLs via CORS. Change `FRONTEND_URLS` to match your setup.
+
+**`.env` file:**
+```env
+NODE_ENV="development"
+HOST=0.0.0.0
+PORT=5000
+FRONTEND_URLS=http://localhost:3000,http://192.168.1.8:3000
+```
+
+---
+
+## Patient Data Extractor Service
+- **Host:** `localhost`  
+- **Port:** `5001`  
+- **Access URL:** [http://localhost:5001](http://localhost:5001)
+
+---
+
+## Selenium Service
+- **Host:** `localhost`  
+- **Port:** `5002`  
+- **Access URL:** [http://localhost:5002](http://localhost:5002)
+
+---
+
+## Payment OCR Service
+- **Host:** `localhost`  
+- **Port:** `5003`  
+- **Access URL:** [http://localhost:5003](http://localhost:5003)
+
+---
+
+## Notes
+- `HOST` controls binding: `localhost` = loopback only, `0.0.0.0` = all interfaces (LAN accessible).
+- `PORT` controls the service's port. Ports never conflict across separate machines — two office PCs can both run on port 5000 with no issue.
+- Frontend uses `VITE_` prefixed variables for client-side access (e.g. `VITE_API_BASE_URL_BACKEND`).
+- In production, traffic is routed through Cloudflare Tunnel — see [Cloudflare Tunnel Setup](../README.md#cloudflare-tunnel-setup-remote-access-per-office) in the main README.
+
+---
+
+**Action for developers:**  
+1. Copy `.env.example` → `.env` inside each app folder.  
+2. Adjust `HOST` / `PORT` if your ports are already taken.  
+3. Set `VITE_API_BASE_URL_BACKEND` to the backend's LAN IP if accessing from other devices.  
+4. Run `npm run dev` from the repo root.