make cgofuse the default for "fs" only on windows. on linux and mac it needs a "cgofuse" build tag.

nostrfs/helpers.go

@@ -0,0 +1,16 @@
+package nostrfs
+
+import (
+	"fiatjaf.com/nostr"
+)
+
+func kindToExtension(kind nostr.Kind) string {
+	switch kind {
+	case 30023:
+		return "md"
+	case 30818:
+		return "adoc"
+	default:
+		return "txt"
+	}
+}