[FEATURE]: Support multiple auth profiles per provider #16866

Feature hasn't been suggested before.

• I have verified this feature I'm about to request hasn't been suggested before.

Describe the enhancement you want to request

• I have searched existing issues and could not find the same request.
• This is a feature request, not a bug report.
• I am opening this issue first for design discussion before any PR.

Problem

OpenCode already has strong provider-agnostic support, but authentication still appears to be effectively single-profile per provider in normal usage.

That makes it difficult to use cases like:

• separate personal and work credentials for the same provider
• separate org/project credentials
• explicit backup credentials for the same provider
• switching between multiple legitimate accounts without rewriting config or re-authing

Proposed solution

Please support multiple named auth profiles per provider.

Example direction:

• anthropic/personal
• anthropic/work
• openai/default
• openai/team-a

Useful capabilities would be:

• store multiple auth profiles for the same provider
• select an active profile
• optionally reference a profile from config / agent config
• switch profiles from CLI or TUI
• keep backward compatibility with the current single-auth setup

Why this belongs in OpenCode

This seems aligned with OpenCode’s provider-agnostic philosophy. It would improve flexibility for real-world usage without coupling the project to any specific provider.

It would also create a clean foundation for future resilience features such as cooldown-aware failover.

Non-goals

I am not asking for hidden quota bypassing. I am asking for explicit, user-configured auth profiles for legitimate multi-account / multi-org setups.

Additional context

A lot of users have separate personal/work credentials or multiple organization-managed credentials for the same provider. Right now that seems harder than it needs to be.