Subagents by name; the activity panel as the reference: header button, compact, tasks

- "Subagents" everywhere a person reads it (chip, popover with Fewest/Most, scheduled task,
  panel); offered per the server's `subagents` on a model or chat where it says it, else as
  before; the fields' most is the server's cap, else 32. No subagent-model setting.
- Panel: always reachable from the header's button; the line above the composer only while
  something runs; Environment for an agent chat; Context with "N until auto-compact" and a
  Compact button (POST /chats/{chat}/compact; a server without it is said so); Background
  tasks under Running with elapsed time and a stop square each, unfolding to kind, step,
  live text and conversation, nested tasks folded under their parent, Finished N folded;
  Room and Plan as sections.
- i18n: 24 new sentences x 8 languages, 9 retired; CHANGELOG [Unreleased].

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

ui/js/main.js

@@ -12,7 +12,7 @@ import { renderSettings, initSettings, scrollToSection } from "./settings.js"
 import { initViewer, onViewer, closeViewer } from "./viewer.js"
 import { initExplorer, showLocal, showFilesTab } from "./explorer.js"
 import { initList, refreshList, markCurrent } from "./list.js"
-import { initChat, openChat, newChat, closeChat, openChatId, chatMenu, statusChanged, draftKind } from "./chat.js"
+import { initChat, openChat, newChat, closeChat, openChatId, chatMenu, statusChanged, draftKind, onThisComputer } from "./chat.js"
 import { initAttach, allowAttach } from "./attach.js"
 import { initPalette, openPalette } from "./palette.js"
 import { initActivity, showPanel, togglePanel, panelOpen } from "./activity.js"
@@ -282,6 +282,9 @@ async function boot() {
     onLayout: (on) => {
       $("shell").dataset.activity = String(on)
     },
+    here: onThisComputer,
+    // The conversation as it now stands: the summary's divider, read again, if it is still open.
+    compacted: (id) => openChatId() === id && openChat(id),
   })
 
   $("new-chat-btn").prepend(icon(ICONS.plus))