Merge pull request 'Update README.md' (#1) from docs into main

Reviewed-on: https://gitea.home.com:3000/TolaMironcenko/dns_service/pulls/1

README.md

@@ -1,7 +1,37 @@
 # DNS_SERVICE (frontend for dnsmasq)
 
-## Build
+- [routes](#routes)
+- [build](#build)
+- [configure](#configure)
+  - [example](#example)
+
+## routes
+
+- `GET` `/` - frontend
+- `GET` `/api/settings` - get all settings
+- `POST` `/api/settings` - set all settings
+- `GET` `/api/settings/file` - get settings file content
+- `POST` `/api/settings/file` - set settings file content
+
+## build
 
 ```shell
 go build
-```
+```
+
+## configure
+
+### example
+
+```
+DNSMASQ_CONFIG=/etc/dnsmasq.conf
+
+ENABLE_TLS=true
+CERT_FILE=/etc/dns_service/dns.home.com.crt
+KEY_FILE=/etc/dns_service/dns.home.com.key
+
+SERVER_ADDRESS=0.0.0.0
+SERVER_PORT=8090
+
+SYSTEM_INITIALIZATION=rc
+```