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.

INSTALL.md

@@ -31,9 +31,9 @@ dashboard, run it from source, or stay on Node 20.
 | npm | 9+ | Comes with Node.js |
 | Claude Code | 2.x+ | Required for hook integration |
 | Git | Any | Cloning the repository, and every lane operation (worktrees, branch/status reads) |
-| **tmux** | 3.x (3.7+ for pane scrollbars) | **Required for the run console** — the browser terminal, `agenthub lanes shell`, and typing `/reload-plugins` into a live pane. See [Step 0](#step-0--system-packages) |
+| **tmux** | 3.x (3.7+ for pane scrollbars) | **Required for the run console** — the browser terminal, `agenthub workspace shell`, and typing `/reload-plugins` into a live pane. See [Step 0](#step-0--system-packages) |
 | Codex CLI | Any | Optional — only for lanes whose tool is `codex` |
-| GitHub CLI (`gh`) | Any | Optional — only for `agenthub lanes ci status` |
+| GitHub CLI (`gh`) | Any | Optional — only for `agenthub workspace ci status` |
 | Python | 3.6+ | Optional — only for `scripts/expand-ts-module-docs.py` (doc generation) |
 
 ---
@@ -42,7 +42,7 @@ dashboard, run it from source, or stay on Node 20.
 
 Node and npm are not enough: `git` backs every lane operation, and **`tmux`
 backs the run console**. The dashboard shells out to the `tmux` binary and has
-no bundled fallback, so without it **Start Run** and `agenthub lanes shell`
+no bundled fallback, so without it **Start Run** and `agenthub workspace shell`
 fail while everything else keeps working.
 
 ```bash
@@ -93,7 +93,7 @@ session explicitly). You can attach to the
 exact same pane from a normal terminal:
 
 ```bash
-agenthub lanes shell             # from inside the lane's directory
+agenthub workspace shell             # from inside the lane's directory
 tmux attach -t agenthub-lane-7   # or by name
 tmux ls                          # every dashboard session is prefixed agenthub-lane-
 ```