Feature request: Support OpenCode ChatGPT OAuth auth.json for Codex/ChatGPT quota tracking

[ovizii]

Hi, I’m using OpenCode with the built-in OpenAI/ChatGPT Plus OAuth login, not an API key. onWatch looks like it can already monitor ChatGPT/Codex quota via the ChatGPT usage endpoints, but it seems to only auto-detect Codex-style credentials from ~/.codex/auth.json or CODEX_HOME/auth.json.

OpenCode stores its OAuth credentials at:

~/.local/share/opencode/auth.json

with a different shape, roughly:

{
  "openai": {
    "type": "...",
    "refresh": "...",
    "access": "...",
    "expires": 1234567890,
    "accountId": "..."
  }
}

onWatch appears to expect Codex-style fields like:

{
  "tokens": {
    "access_token": "...",
    "refresh_token": "...",
    "account_id": "..."
  }
}

Could onWatch support OpenCode’s ChatGPT OAuth credential file directly, either by auto-detecting ~/.local/share/opencode/auth.json or by allowing a provider/profile config that maps this format?

This would let OpenCode users monitor their ChatGPT Plus/Pro quota/reset without setting up separate Codex auth or copying tokens into another file.