feat: workspaces own their sessions; desktop parity; sidebar and settings cleanup

Workspace sessions (docs/plans/desktop-parity, phases 1-5 and 7):
- sessions.lane_id: a workspace lists only the sessions its panes held,
  stamped by bindRunSession (first writer wins, nested `claude -p`
  excluded); GET /api/sessions?lane=&archived=
- session row state dot, double-click rename, archive (sessions.archived_at,
  hides only); the activity bar's duplicate Sessions tab removed
- Fork beside Resume (--fork-session, Claude only), Ctrl/Cmd+click a live
  session opens it in a second pane, a diff line's comment is pasted into
  the workspace's last-focused pane (lib/panePaste.ts)

dashboard_runs stability:
- a pane's previous run is archived as <pane>@<started_at> instead of being
  overwritten by INSERT OR REPLACE
- a run is flagged abandoned only once its tmux session is gone, at boot and
  on the run-heal beat (panes outlive a server restart)

UI:
- sidebar: no footer, language or theme block; small collapse button in the
  brand corner; version + update check in the connection details modal, a
  status-bar dot while a release is out; language in Settings -> General
- one Switch component for every switch, the themed Checkbox for every
  checkbox (no native checkboxes)

Also: AI Tools catalog trimmed to 10 built-ins (custom-file prompt modes
tested through fixtures), and the workspace plans under docs/plans/ (the
multi-user server plan lives in the AgentHub-Server repo).

client/src/components/lanes/WorkspaceHome.tsx

@@ -2,9 +2,10 @@
  * @file WorkspaceHome — what `/workspace?lane=<id>` opens on, shaped like a
  * Claude Desktop project page: the name, a prompt box that starts a NEW
  * session in the first free pane slot (0–3, `POST /api/lanes/:id/start`) and
- * then opens it (`&run=<runId>`), the workspace's Recents (a live session
- * opens its pane, any other its transcript — nothing is resumed), and on the
- * right its context: Instructions, Memory (read-only), Context files and
+ * then opens it (`&run=<runId>`), the workspace's Recents — the sessions it
+ * owns and has not archived (`?lane=&archived=0`, with each one's state dot),
+ * then the archived ones folded with Unarchive; a live session opens its pane,
+ * any other its transcript, nothing is resumed — and on the right its context: Instructions, Memory (read-only), Context files and
  * Folders (`GET/PUT/POST/DELETE /api/lanes/:id/sources…`, see
  * server/lib/lane-sources.js). Folder suggestions are the repo's untracked
  * worktrees from `GET /api/projects`, filtered by Settings → Worktrees.
@@ -14,7 +15,16 @@
 import { useEffect, useRef, useState } from "react";
 import { useTranslation } from "react-i18next";
 import { useNavigate } from "react-router-dom";
-import { FileText, Folder, MoreHorizontal, Pencil, Play, Plus, X } from "lucide-react";
+import {
+  ArchiveRestore,
+  FileText,
+  Folder,
+  MoreHorizontal,
+  Pencil,
+  Play,
+  Plus,
+  X,
+} from "lucide-react";
 import {
   api,
   type LaneMemoryFile,
@@ -31,7 +41,7 @@ import { Select } from "../Select";
 import { MarkdownPreview } from "../MarkdownPreview";
 import { WorkspaceRowMenu, type WorkspaceMenuAction } from "./WorkspaceRowMenu";
 import { workspaceName } from "./WorkspaceRow";
-import { liveRunFor } from "./WorkspaceSessionList";
+import { liveRunFor, SessionFold, sessionDot, useSessionPage } from "./WorkspaceSessionList";
 
 /** The tmux session a pane slot of a lane owns (server/lib/pty-run.js). */
 export function paneRunId(laneId: number, slot: number): string {
@@ -103,6 +113,8 @@ function HomeBody({
 
   // A new pane, a pane gone, a session id learned — all move these lane fields.
   const runKey = `${lane.status}:${lane.session_id}:${lane.run_id}`;
+  // Bumped after a session is unarchived, so the lists re-read.
+  const [version, setVersion] = useState(0);
   useEffect(() => {
     let live = true;
     api.run
@@ -110,13 +122,17 @@ function HomeBody({
       .then((r) => live && setLiveRuns(r.items))
       .catch(() => undefined);
     api.sessions
-      .list({ cwd: lane.cwd, tool: lane.tool, limit: 30 })
+      .list({ lane: lane.id, archived: false, limit: 30 })
       .then((r) => live && setSessions(r.sessions))
       .catch(() => live && setSessions([]));
     return () => {
       live = false;
     };
-  }, [lane.id, lane.cwd, lane.tool, runKey]);
+  }, [lane.id, runKey, version]);
+  const archived = useSessionPage(
+    { lane: lane.id, archived: true, limit: 30 },
+    `${runKey}:${version}`
+  );
 
   useEffect(() => {
     let live = true;
@@ -362,11 +378,7 @@ function HomeBody({
                   onClick={() => openSession(s)}
                   className="flex w-full items-center gap-3 py-2.5 text-left hover:bg-surface-3"
                 >
-                  <span
-                    className={`h-2 w-2 shrink-0 rounded-full ${
-                      live ? "bg-status-success" : "border border-fg-muted"
-                    }`}
-                  />
+                  <span className={`h-2 w-2 shrink-0 rounded-full ${sessionDot(s, live)}`} />
                   <span className="min-w-0 flex-1 truncate text-sm text-fg-primary">
                     {s.name || s.id.slice(0, 8)}
                   </span>
@@ -383,6 +395,17 @@ function HomeBody({
             );
           })}
         </ul>
+        <div className="mt-2">
+          <SessionFold
+            testId={`workspace-archived-${lane.id}`}
+            page={archived}
+            label={(count) => t("tree.archived", { count })}
+            actionLabel={t("tree.unarchive")}
+            actionIcon={<ArchiveRestore className="h-3.5 w-3.5" />}
+            onAction={(s) => api.sessions.patch(s.id, { archived: false })}
+            onDone={() => setVersion((v) => v + 1)}
+          />
+        </div>
       </div>
 
       <aside data-testid="workspace-context" className="card w-80 shrink-0 self-start p-0">