Add 'repo' to MentionType across all editor types, include repos in the
@ trigger pool, add repo badge (green chip), Repos section in the
mention dropdown, and MentionBadge styles. Wire projectRepos from
room context into IMEditor mentionItems.
CommandPalette: replace workspaceProjects with getCurrentUserProjects
(no workspace dependency so it works outside WorkspaceProvider).
Repos fetched per-project to preserve correct /repository/ns/repo
routes. Keyboard shortcut correctly matches Ctrl+Alt+F / Cmd+Ctrl+F.
sidebar-user: fix notification button layout — bell icon and label
now on the same row instead of separate stacked elements.