nlm-login-only-valid-auth-path-for-notebooklm-upstream

For notebooklm-mcp-cli, the only reliable auth initialization paths are: (1) docker exec -it notebooklm-mcp nlm login for interactive Chrome CDP browser login, or (2) the save_auth_tokens MCP tool to inject freshly captured tokens. The refresh_auth MCP tool alone cannot establish initial auth from migrated cookies. Document this as the operational runbook step whenever the container is rebuilt or cookies expire.