docs: simplify README by removing separate Local Development section

The Docker Compose setup already supports hot reload, so a separate
local dev section is unnecessary. Mention hot reload inline instead.

https://claude.ai/code/session_01JTbjLrkLpw9qMsaLup2Kqa

Author: claude

README.md

@@ -18,22 +18,7 @@ docker compose exec backend pnpm migrate
 docker compose exec backend pnpm seed    # Optional: populate with sample data
 ```
 
-The app is available at `http://localhost:8080` (nginx reverse proxy).
-
-## Local Development
-
-For faster iteration on the Node.js apps (hot reload without container overhead):
-
-```bash
-# Prerequisites: Node.js 24+, pnpm 8+
-docker compose up -d
-pnpm install
-pnpm migrate
-pnpm seed                # Optional: populate with sample data
-pnpm dev
-```
-
-Frontend runs at `http://localhost:5173`, backend at `http://localhost:3000`.
+The app is available at `http://localhost:8080` (nginx reverse proxy). This setup also works well for development — source code is mounted into the containers with hot reload enabled.
 
 ## Documentation