feat(web,server): embed статики SPA + fallback, монтирование в cmd/server

cmd/server/main.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"log"
 	"net/http"
+	"strings"
 
 	"github.com/jackc/pgx/v5/pgxpool"
 
@@ -14,6 +15,7 @@ import (
 	"github.com/vasyakrg/dns-autoresolver/internal/provider/selectel"
 	"github.com/vasyakrg/dns-autoresolver/internal/service"
 	"github.com/vasyakrg/dns-autoresolver/internal/store"
+	"github.com/vasyakrg/dns-autoresolver/internal/web"
 )
 
 func main() {
@@ -42,9 +44,27 @@ func main() {
 
 	svc := service.New(st, st, reg, cipher)
 	a := &api.API{Svc: svc, Store: st, Cipher: cipher, Reg: reg}
+	apiRouter := api.NewRouter(a)
+
+	webHandler, err := web.Handler()
+	if err != nil {
+		log.Printf("web: static UI unavailable: %v", err)
+	}
+
+	mux := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if strings.HasPrefix(r.URL.Path, "/api/") {
+			apiRouter.ServeHTTP(w, r)
+			return
+		}
+		if webHandler != nil {
+			webHandler.ServeHTTP(w, r)
+			return
+		}
+		http.NotFound(w, r)
+	})
 
 	log.Printf("listening on %s", cfg.ListenAddr)
-	if err := http.ListenAndServe(cfg.ListenAddr, api.NewRouter(a)); err != nil {
+	if err := http.ListenAndServe(cfg.ListenAddr, mux); err != nil {
 		log.Fatal(err)
 	}
 }