OptionalmcpC058: activate the MCP OAuth server by declaring its SCOPE SET — the loginPage/consentPage/resource URLs are DERIVED
from LIVE_BASE_URL (no host boilerplate). This is the single-source authoring path.
OptionalmcpLEGACY: the full MCP OAuth URL block. Prefer mcpScopes (URLs derived). Kept for back-compat with hand-authored URLs.
auth's serviceOpts: optionally activate the MCP OAuth server (Better Auth
mcp()plugin).