OAuth-token checks tightened for Grove config and unix-socket auth

What

• The function that decides whether to check or fetch "Grove" config now also requires either a specific OAuth scope or a bare CLAUDE_CODE_OAUTH_TOKEN with no other credential source present, in addition to its existing check.
• The diagnostic message shown when ANTHROPIC_UNIX_SOCKET is set was reworded to explicitly state whether CLAUDE_CODE_OAUTH_TOKEN is also set, clarifying that without it, requests on that socket carry no claude.ai login.

Why

This makes it clearer and more consistent when Claude Code relies on CLAUDE_CODE_OAUTH_TOKEN for authentication, both for internal config fetching and in the diagnostics a user sees.