[AUTH] OAuth support

[diegosc78]

CONTEXT:

In open webui it's allowed to configure connections with terminal using several auth methods. See https://github.com/open-webui/open-webui/blob/01f4282f1ffe0d6212f58d3afbeae21fffd0c4be/backend/open_webui/utils/tools.py#L1350-L1359

Specifically it's allowed forward oauth token

PROPOSAL:

Implement OAuth token support (aditional to simple api-key). This implies:

• Receive it in authentication bearer header
• Validate and refresh it against SSO
• Use it to decode user id (equivalent to X-user-id header)

ADVANTAGE:

• Higher security
• Easier to implement in the future connections from commands inside openterminal (eg. python scripts created by LLM) to other systems (eg. MCP) using that session token (propagating user session to backyard)