remove $PORT, use config for listen port

MCP's pasta port mapping maps host:randomport to container:routeport.
The app must listen on the route's port (443) inside the container,
configured via HTTP_PORT in kls.conf.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

main.go

@@ -6,7 +6,6 @@ import (
 	"log"
 	"net"
 	"net/http"
-	"os"
 
 	"git.wntrmute.dev/kyle/goutils/config"
 	"git.wntrmute.dev/kyle/goutils/die"
@@ -30,15 +29,10 @@ func main() {
 	srv := &server{db: db}
 	http.Handle("/", srv)
 
-	var addr string
-	if port := os.Getenv("PORT"); port != "" {
-		addr = ":" + port
-	} else {
-		addr = net.JoinHostPort(
+	addr := net.JoinHostPort(
 		config.Get("HTTP_ADDR"),
 		config.GetDefault("HTTP_PORT", "8000"),
 	)
-	}
 	log.Print("listening on ", addr)
 	log.Fatal(http.ListenAndServe(addr, nil))
 }