[relay] Feature/relay integration (#2244)

This update adds new relay integration for NetBird clients. The new relay is based on web sockets and listens on a single port.

- Adds new relay implementation with websocket with single port relaying mechanism
- refactor peer connection logic, allowing upgrade and downgrade from/to P2P connection
- peer connections are faster since it connects first to relay and then upgrades to P2P
- maintains compatibility with old clients by not using the new relay
- updates infrastructure scripts with new relay service

relay/auth/hmac/validator.go

@@ -0,0 +1,33 @@
+package hmac
+
+import (
+	"fmt"
+	"hash"
+	"time"
+
+	log "github.com/sirupsen/logrus"
+)
+
+type TimedHMACValidator struct {
+	*TimedHMAC
+}
+
+func NewTimedHMACValidator(secret string, duration time.Duration) *TimedHMACValidator {
+	ta := NewTimedHMAC(secret, duration)
+	return &TimedHMACValidator{
+		ta,
+	}
+}
+
+func (a *TimedHMACValidator) Validate(algo func() hash.Hash, credentials any) error {
+	b, ok := credentials.([]byte)
+	if !ok {
+		return fmt.Errorf("invalid credentials type")
+	}
+	c, err := unmarshalToken(b)
+	if err != nil {
+		log.Debugf("failed to unmarshal token: %s", err)
+		return err
+	}
+	return a.TimedHMAC.Validate(algo, c)
+}