[feature]: Opencode Go without workspace ID and auth cookie

[ak-specto]

Pre-flight checks

• I searched existing issues and did not find a duplicate request.
• I reviewed current behavior on the production released OpenCode version.

OpenCode version reviewed

1.14.29

Problem statement

Currently to setup Opencode Go quota information in this plugin, we need to add certain env values:

export OPENCODE_GO_WORKSPACE_ID="your-workspace-id"
export OPENCODE_GO_AUTH_COOKIE="your-auth-cookie"

Proposed change

Is there a way to query the local DB and configurations, without these values. The Openusage application doesn't require this, yet it shows the up to date information about the Opencode Go usage, I found the source file which queries this information: https://github.com/robinebers/openusage/blob/main/plugins/opencode-go/plugin.js

...
  const AUTH_PATH = "~/.local/share/opencode/auth.json";
  const DB_PATH = "~/.local/share/opencode/opencode.db";
...

Looks like it queries the information automatically.
Is there an option for this plugin to do the same?

Alternatives considered

No response

Acceptance criteria

No response

[slkiser]

This could be added, it is a local estimate though and is something I added for some of the Chinese providers.

But not a big fan since even when I compare my local usage with the actual billing, somehow I get small discrepancies.

If others request this, I'd be open to considering it