git:20260608.a859968 to git:20260608.a548c2e

8 added, 1 removed. Audit A to A.

React SPA connecting to the server via WebSocket (`useChat` hook).

- - Three chat modes: `solo` (few messages), `sidebar`, `floating` (popover). Switches automatically based on message count and viewport width.

+ ## Entities

+ - **Space** — Top-level container. Has a name and contains widgets and a chat. One space is active at a time.

+ - **Widget** — A configurable card inside the space's main area. Displayed in a grid. Visible when the chat has moved out of solo mode.

+ - **Chat** — The agent conversation. Contains a scrollable message list and an input. Three modes: solo (centered, no widgets), sidebar (pinned right of widgets), floating (popover). Starts solo, switches after 5 messages based on viewport width.

+ ## Conventions

- UI components in `components/ui/` are shadcn built on Base UI React.

- `lib/cn.ts` is `clsx` + `tailwind-merge`.