New plugin, separate from the existing X plugin, pointing at X's hosted
ads MCP server (https://ads-api.x.com/mcp). Auth is per protected
resource: ads-api.x.com advertises its own OAuth metadata and scopes
(ads.read, ads.write), so it cannot share the X plugin's authorization
even though it reuses the same OAuth client ID.
Co-authored-by: Cursor <cursoragent@cursor.com>