Notification preferences settings with tabbed channel matrix table for Email, Slack, and In-app

reui/settings-11

Notification settings grouping events under Projects, Messages, Reports, and System tabs, each a table with per-row Email/Slack/In-app checkboxes. Uses ReUI Tabs (line), Table, Checkbox. For alert preferences and channel opt-in.

Paid component: its registry needs a licence from the library, so install it from their site.