- ChatArea: .empty-chat custom icon+text -> GnEmptyState card
  (keep .empty-chat wrapper only for centering)
- CardGrid: inline Teleport modal (overlay/close/scroll bespoke chrome
  removed) -> GnModal; .card-modal/.card-modal-title class names kept
  inside the new DOM (test contract); kit header slot renders the title
- WelcomeScreen: typography aligned to kit (30px h1, 14px base),
  profile cards get -radius-md, dead .profile-icon style dropped
- CardGrid test: mount with the kit plugin (GnModal resolves),
  two nextTicks for the post-flush open watcher

Verified: vitest 111 passed, build OK, welcome screenshot unchanged
(modal/empty-state visually checked after final build)