feat: add passkey creation functionality

pkg/common/passkeys/credentials_link.go

@@ -0,0 +1,15 @@
+package passkeys
+
+//
+// import (
+// 	"github.com/go-webauthn/webauthn/protocol"
+// 	"github.com/labstack/echo/v4"
+// 	"github.com/onsonr/sonr/crypto/mpc"
+// )
+//
+// func Link(c echo.Context, handle string, ks mpc.Keyset) protocol.PublicKeyCredentialCreationOptions {
+// 	origin := c.Request().Host
+// 	svcName := c.Request().Host
+// 	addr := ks.Address()
+// 	return c.String(200, origin+" "+svcName+" "+addr+" "+handle)
+// }