List broken link presets

List the organization's Broken Links Checker global configurations (presets): the named scan schedules applied to websites (what is checked: internal links, external links, mixed content; render mode), with how many websites use each and which one is the default for new websites. The id is what the `preset_broken_link` field of "Create connection plugin" (`POST /api/public/v1/connection-plugins`) takes. Response fields: `id`, `name`, `status` (enabled, disabled), `is_default`, `frequency`, `start_hour`, `timezone`, `day_week`, `day_month`, `check_internal`, `check_external`, `check_mixed_content`, `mode` (plain, render), `sites_count` (opt in with `fields[preset-broken-links]=sites_count`), `created_at`, `updated_at`.