Same accordion pattern as stream: card-row gets entity-exp markup,
selectEntity/expandInline/dismissPeek/Escape all handle .card-row.
Fullscreen expand works for both views.
Replace bottom-sheet peek with inline accordion at ≤900px.
Entries expand in-place with grid-template-rows animation (0.2s).
Body clamped to 3 lines; fullscreen uncaps it.
Selection toggles DOM classes instead of re-rendering for fluid j/k nav.
Grid forced to single-column at ≤900px for all panel states.
Resize handles hidden, transitions killed to prevent slivers.
Peek pane gets mobile toolbar (expand/dismiss buttons).
Escape dismisses peek at any viewport. Z toggles full-screen
peek at mobile instead of no-op zen toggle.
lerko