Add relayinfo package and utility modules for NIP-11 support

Introduce the `relayinfo` package with `NIP-11` utilities, including `Fees`, `Limits`, and `NIPs` structures. Add utility modules for handling numbers, timestamps, and kinds. Integrate functionality for fetching and managing relay information.

app/listener.go

@@ -0,0 +1,29 @@
+package app
+
+import (
+	"net/http"
+
+	"lol.mleku.dev/log"
+	"next.orly.dev/app/config"
+)
+
+type Listener struct {
+	mux    *http.ServeMux
+	Config *config.C
+}
+
+func (l *Listener) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	log.I.F("path %v header %v", r.URL, r.Header)
+	if r.Header.Get("Upgrade") == "websocket" {
+		l.HandleWebsocket(w, r)
+	} else if r.Header.Get("Accept") == "application/nostr+json" {
+		l.HandleRelayInfo(w, r)
+	} else {
+		http.Error(w, "Upgrade required", http.StatusUpgradeRequired)
+	}
+}
+
+func (l *Listener) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
+	log.I.F("websocket")
+	return
+}