internal/handler/index.go

package handler

import (
_ "embed"
"net/http"
)

//go:embed index.html
var indexHTML []byte

func HandleIndex(w http.ResponseWriter, r *http.Request) {
if r.URL.Path != "/" {
http.NotFound(w, r)
return
}
w.Header().Set("Content-Type", "text/html; charset=utf-8")
w.Write(indexHTML)
}