A chat app's shape: sidebar, a new chat as a chat page, the chat's settings as composer chips

- Sidebar: New chat, search, Scheduled, Files, the chats of both kinds by day (Today, Earlier),
  Settings with the account at the foot; folds away (Ctrl+B), a drawer on a narrow window.
- A new chat is the chat page empty: a greeting, Agent or Chat, and the composer.
- The composer is a card: the text, then attach, the chips (folder and mode for an agent chat,
  model with its picture, effort as the model offers it, the team's size), and a round Send that
  Stop replaces while a reply is written. An open chat's chips change the chat.
- Messages: the person's in a bubble on the right with attached pictures as thumbnails, a reply
  full width; thinking and tool calls as compact rows that unfold.
- Activity: a chip above the composer for every open chat, the panel on the right as before.
- The agent: a chip in the title bar opening its state and the one thing to do about it; "This
  computer is not linked yet" with Link this computer right above the composer of an agent chat,
  and "refused" only with the server's reason.
- Files: a page with the two trees as tabs. Settings: grouped, the groups listed beside them.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

ui/js/models.js

@@ -14,7 +14,7 @@ import { menu } from "./popup.js"
 // so a missing picture is not asked for again with every redraw).
 const pictures = new Map()
 
-function picture(path) {
+export function picture(path) {
   if (!pictures.has(path)) pictures.set(path, invoke("model_image", { path }).catch(() => null))
   return pictures.get(path)
 }