feat: device authorization RFC 8628 (#5646)

* device auth: implement the write events

* add grant type device code

* fix(init): check if default value implements stringer

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Co-authored-by: adlerhurst <silvan.reusser@gmail.com>

cmd/defaults.yaml

@@ -233,6 +233,8 @@ OIDC:
       Path: /oidc/v1/end_session
     Keys:
       Path: /oauth/v2/keys
+    DeviceAuth:
+      Path: /oauth/v2/device_authorization
 
 SAML:
   ProviderConfig: