feat: workspace aliases, tab groups of split panes, native path picker (v2.1.0)

- /api/workspaces and `agenthub workspace(s)` / `--workspace` as aliases of
  /api/lanes and `agenthub lanes` / `--lane`; old names print one stderr note.
  REPL `help lanes|workspace|workspaces` resolves through the aliases.
- A workspace holds up to ten sessions (slots 0-9); every console tab is a
  group of 1-4 split panes (PaneGroups, agenthub.workspace.paneLayout);
  parseGroups keeps the stored active tab when an earlier one is dropped.
- Browse button beside path fields: POST /api/lanes/pick-path opens the OS
  picker on the server's desktop — loopback only and no forwarding header
  (EREMOTE), a display failure is ENODIALOG not a Cancel, the dialog is
  killed when the request closes, a folder field falls back to the in-app
  browser on any failure.
- Changes rail counts chip, image viewer (/git/raw), status bar session
  counts and per-day cost (`date=` on /api/pricing/cost).
- /agenthub-open and /agenthub-doctor run from the INSTALLED build
  (supersededBy), doctor offers fixes behind two confirmations; plugin-open
  treats a locked bootstrap as non-fatal.
- New-terminal shell waits for the first attach (issue #55).
- repo-onboarding / debug-live-issue skills removed.
- OpenAPI: pick-path, lane/date on /pricing/cost, tool on /run/history,
  /api/workspaces mount.

client/src/components/lanes/WorkspaceRowMenu.tsx

@@ -1,29 +1,20 @@
 /**
  * @file WorkspaceRowMenu — the sidebar workspace row's context menu, opened at
  * the pointer (right-click) or under the row's `⋯` button. Every item is an
- * existing call: Start (`POST /api/lanes/:id/start`, the free tab the server
- * picks — then the session opens, `onAction("started", runId)`) / Stop
- * (`stop`, every tab of the workspace — counted from `GET /api/run` when the
- * menu opens, and confirmed: "Stop N sessions?"),
- * Rename (the row's inline field), New workspace here (the Add modal prefilled),
- * Copy path, and Reset/Remove through `DestructiveLaneModal` — Reset only on a
+ * existing call: Rename (the row's inline field), New workspace here (the
+ * Add modal prefilled), Copy path, and Reset/Remove through `DestructiveLaneModal` — Reset only on a
  * managed lane. The server's guards are the real ones; the menu only hides
  * what the lane's kind or tool makes meaningless. The shell (position,
  * Escape / outside-click close) is `ContextMenu`.
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 
-import { useEffect, useState } from "react";
 import { useTranslation } from "react-i18next";
-import { api } from "../../lib/api";
 import type { Lane } from "../../lib/types";
 import { ContextMenu, MenuItem, MenuSeparator } from "../ContextMenu";
-import { confirmDialog } from "../../lib/confirm";
 import { copyText } from "../../lib/clipboard";
-import { toast } from "../../lib/toast";
-import { startInFreeTab } from "./startSession";
 
-export type WorkspaceMenuAction = "rename" | "new-here" | "reset" | "remove" | "started";
+export type WorkspaceMenuAction = "rename" | "new-here" | "reset" | "remove";
 
 export function WorkspaceRowMenu({
   lane,
@@ -36,62 +27,12 @@ export function WorkspaceRowMenu({
   x: number;
   y: number;
   onClose: () => void;
-  /** Items the tree itself carries out (rename field, modals, selection);
-   *  `started` comes with the run it opened. */
-  onAction: (action: WorkspaceMenuAction, runId?: string) => void;
+  /** Items the tree itself carries out (rename field, modals). */
+  onAction: (action: WorkspaceMenuAction) => void;
 }) {
   const { t } = useTranslation("lanes");
-  // Every live tab of the workspace — slot 0 alone undercounts a split.
-  const [liveCount, setLiveCount] = useState<number | null>(null);
-  useEffect(() => {
-    let alive = true;
-    api.run
-      .list()
-      .then(
-        (r) =>
-          alive &&
-          setLiveCount(
-            (r.items ?? []).filter((x) => x.laneId === lane.id && x.status === "running").length
-          )
-      )
-      .catch(() => undefined);
-    return () => {
-      alive = false;
-    };
-  }, [lane.id]);
-  const live = liveCount === null ? !!lane.run_id || lane.status === "running" : liveCount > 0;
-
-  const stop = async () => {
-    onClose();
-    const n = liveCount ?? 1;
-    if (
-      !(await confirmDialog({
-        title: t("menu.stopTitle", { count: n }),
-        message: t("menu.stopBody"),
-        confirmLabel: t("menu.stop"),
-        destructive: true,
-      }))
-    )
-      return;
-    try {
-      await api.lanes.action(lane.id, "stop");
-    } catch (err) {
-      toast.error(err);
-    }
-  };
-  const start = async () => {
-    onClose();
-    try {
-      onAction("started", await startInFreeTab(lane.id, { prompt: "" }));
-    } catch (err) {
-      toast.error(err);
-    }
-  };
   return (
     <ContextMenu x={x} y={y} onClose={onClose} testId={`workspace-row-menu-${lane.id}`}>
-      <MenuItem onSelect={() => void (live ? stop() : start())}>
-        {live ? t("menu.stop") : t("menu.start")}
-      </MenuItem>
       <MenuItem onSelect={() => onAction("rename")}>{t("menu.rename")}</MenuItem>
       <MenuItem onSelect={() => onAction("new-here")}>{t("menu.newHere")}</MenuItem>
       <MenuItem