[Bug]: Issue authenticating to BQ via OAuth on Windows for CLI tools

### What happened?

Reported in Slack: https://getdbt.slack.com/archives/C08NGJYD563/p1759988417219589

It looks like when the person runs dbt Core in a terminal, dbt leverages the credentials created by `gcloud auth`.
But when they try to run the CLI tools via the MCP server they get the message

```
05:53:02 Encountered an error:
Database Error
Caller does not have required permission to use project XXXXX. Grant the caller the roles/serviceusage.serviceUsageConsumer role, or a custom role with the serviceusage.services.use permission, by visiting https://console.developers.google.com/iam-admin/iam/project?project=XXXXX and then retry. Propagation of the new permission may take a few minutes.
```

I am wondering if this is not a bug specific to Windows.

When we do a `gcloud auth` the credentials are saved in `~/.config/gcloud` for Unix/MacOS and in `%APPDATA%\gcloud` for Windows, and I am wondering if there is no Windows specificity that makes running the CLI from Windows not point to the correct directory.

### Steps to Reproduce

.

### Deployment

Local MCP server

### Environment

- OS: WIndows

### Relevant log output

```shell

```