- Add components/RoomMessageBlock.svelte to render a block header (profile picture, display name, timestamp) and
group consecutive messages from the same user.
- Refactor src/app/components/RoomItem.svelte to support grouped-mode (isGrouped) and remove per-message header/spacing, keep
reactions/actions intact.
- Update message feed processing in:
- src/routes/spaces/[relay]/[h]/+page.svelte
- src/routes/spaces/[relay]/chat/+page.svelte
to emit message-block items (respecting the existing 3-minute gap rule) and render blocks via RoomMessageBlock.