You can safely store secrets in Teamogy.
In registry which is "ADAPTER...." you will use the button "Secret". Then you can add new secret as a new line. You need to set the name, secret value and set the url that this secret key will be used for. After saving, the value will be replaced by string: {{secret:your_secret_name}} - this string you can use securely in the adapter. When the server performs an API operation, it checks if the URL is the same as the secret URL (to avoid sending the secret key to the wrong API), and if so, replaces {{secret:your_secret_name}} with the actual secret key value.
Once the secret has been stored, there is no way for the Teamogy user to access its value. But if the secret value is to be changed, it is possible to overwrite the value of the secret to a new value in the dialog for saving secrets.