docs: update README with usage instructions

README.md

@@ -1,3 +1,21 @@
 # wol-api
 
-Wake-on-LAN API in Bun
+Wake-on-LAN API in Node.js
+
+## Running
+1. `npm install`
+2. `npm run start`
+
+## Usage
+
+### POST to `/wake`
+```bash
+curl -X POST -H "Content-Type: application/json" -d '{
+  "mac": "00:AA:BB:CC:DD:EE"
+}' http://localhost:9999/wake
+```
+
+### GET to `/wake`
+```bash
+curl http://localhost:9999/wake?mac=00:AA:BB:CC:DD:EE
+```