Harden dev environment configuration

README.md

@@ -76,9 +76,9 @@ A comprehensive SAAS application for managing recruiter workflows, built with mo
    ```
 
 5. **Access the application**
-   - Frontend: http://localhost:3000
-   - Backend API: http://localhost:3001
-   - Database: localhost:5432
+   - Frontend: http://localhost:12000
+   - Backend API: http://merchantsofhope-supplyanddemandportal-backend:3001 (inside Docker network) or http://localhost:3001 when running natively
+   - Database: merchantsofhope-supplyanddemandportal-database:5432 (inside Docker network)
 
 ### Alternative: Native Node.js workflow
 
@@ -98,7 +98,7 @@ cd ../frontend
 npm start
 ```
 
-Ensure a PostgreSQL instance is running and the `DATABASE_URL` in `.env` points to it.
+Ensure a PostgreSQL instance is running and the `DATABASE_URL` in `.env` points to it. The frontend `.env.development` file pins the dev server to `0.0.0.0:12000` so it matches the Docker behaviour.
 
 ### Demo Accounts