[Docs][dirctl] Authentication does not work out‑of‑the‑box for remote Directory deployments

[pedro-fernandez-dell]

Issue Description

When a Directory node is deployed to a remote environment (e.g. a cloud provider or remote Kubernetes cluster), most of the documented authentication methods for dirctl stop working when the CLI is executed outside the target cluster.
For example:

Following the deployment guide at
https://github.com/agntcy/dir-staging
Deploying a Directory node on a cloud‑hosted Kubernetes cluster
Attempting to use dirctl from a local machine (outside the cluster)

In this scenario, the authentication methods described in the documentation
https://github.com/agntcy/docs/blob/main/docs/dir/directory-cli.md#authentication
do not work out of the box when used remotely.
As a result, users are able to deploy a Directory node successfully, but are unable to authenticate dirctl from outside the cluster without additional, undocumented steps.

This has the potential to create friction for:

• First‑time users and early adopters
• Users evaluating AGNTCY Directory in real‑world (non‑local) deployments
• Exploration, testing, and validation workflows that assume local CLI usage against a remote cluster

Overall, this can hinder adoption and experimentation with AGNTCY Directory deployments beyond local or in‑cluster use cases.

Prposed Solution

One (or more) of the following could improve the experience:

1. Documentation improvement
   Add a dedicated section describing how to authenticate dirctl when it is executed outside the target cluster, including:

• Supported authentication mechanisms
• Required configuration or credentials
• Common pitfalls for remote usage

2. CLI enhancement (optional / opinionated)
   Introduce a native dirctl authentication command or workflow explicitly designed for remote access scenarios.

Affected Component

Directory

Checklist

• I have read the contributing guidelines.
• I have verified this does not duplicate an existing issue.