Pinned chats and chat folders in the sidebar

The server's /api/v2 sets `pinned` on PATCH /chats/{id} and makes, renames and deletes
folders. The sidebar lists the pinned chats first, then the folders (nested, folded as the
server keeps them, each counting its chats), then the rest by day; searching lists every
match flat. A chat's menu pins it and moves it (to no folder, any folder, or a new one);
a folder's menu renames it, makes one inside it, deletes it (its chats stay). Tests F8.

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

ui/js/chat.js

@@ -17,7 +17,7 @@ import { avatar, agentsControl, teamPossible, namedOnly, subagentsCap, noteSubag
 import { readyIds, sending, sent, discard } from "./attach.js"
 import { watchActivity, activityChanged, planList, activityButton, treeChanged } from "./activity.js"
 import { agentBlock, agentReady, agentState, onAgentChange } from "./agent.js"
-import { folderName, listed } from "./list.js"
+import { folderName, listed, folderTree, newFolder } from "./list.js"
 import { unarchive } from "./archived.js"
 import { isProgress, progressLine, progressTicks } from "./progress.js"
 import { aimTerminal, terminalButton, terminalOpen, toggleTerminal } from "./terminal.js"
@@ -1033,6 +1033,10 @@ export function chatMenu(anchor, chat) {
   const base = ctx.status()?.server
   const mayDelete = ctx.me()?.permissions?.["chat.delete"] !== false
   const items = [{ label: t("Rename…"), run: () => renameChat(chat) }]
+  if (!chat.archived) {
+    items.push({ label: chat.pinned ? t("Unpin chat") : t("Pin chat"), run: () => setChat(chat, { pinned: !chat.pinned }) })
+    items.push({ label: t("Move to folder…"), run: () => moveMenu(anchor, chat) })
+  }
   if (chat.kind === "agent" && chat.device_session_id) items.push({ label: t("Continue in a terminal…"), run: () => continueInTerminal(chat) })
   if (base) items.push({ label: t("Open in the web interface"), run: () => openLink(`${base}/chat/${encodeURIComponent(chat.id)}`) })
   items.push(null, chat.archived ? { label: t("Restore chat"), run: () => unarchiveChat(chat) } : { label: t("Archive chat"), run: () => archiveChat(chat) })
@@ -1068,6 +1072,34 @@ export async function continueInTerminal(chat) {
   })
 }
 
+/** Where a chat can go: no folder, any of the account's, or a new one. */
+function moveMenu(anchor, chat) {
+  const here = chat.folder_id || ""
+  menu(anchor, [
+    { label: t("No folder"), checked: !here, run: () => here && setChat(chat, { folder_id: null }) },
+    ...folderTree().map(({ folder, depth }) => ({ label: `${"\u2003".repeat(depth)}${folder.name}`, checked: folder.id === here, run: () => folder.id !== here && setChat(chat, { folder_id: folder.id }) })),
+    null,
+    {
+      label: t("New folder…"),
+      run: async () => {
+        const id = await newFolder()
+        if (id) setChat(chat, { folder_id: id })
+      },
+    },
+  ])
+}
+
+/** A change to a chat from its menu (pinned, its folder): the list drawn again from the server. */
+async function setChat(chat, body) {
+  try {
+    const r = await patch(`/chats/${encodeURIComponent(chat.id)}`, body)
+    if (open?.chat?.id === chat.id && r?.chat) open.chat = r.chat
+    ctx.changed(r?.chat)
+  } catch (err) {
+    alertIn(why(err))
+  }
+}
+
 async function renameChat(chat) {
   const title = await ask({ title: t("Rename chat"), value: chat.title || "", ok: t("Rename"), cancel: t("Cancel") })
   if (!title || title === chat.title) return