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.

plugins/agenthub/commands/agenthub-update.md

@@ -23,29 +23,31 @@ else
 fi
 ```
 
-That downloads the new version into `~/.claude/plugins/cache/` but does not
-take effect in *this* session — Claude Code only re-resolves `${CLAUDE_PLUGIN_ROOT}`
-on `/reload-plugins` (a REPL-only action, not scriptable from a command). Say
-so plainly: **tell the user to run `/reload-plugins` now**, then either
-re-run `/agenthub-update` (this time the bootstrap step below runs against the new
-version) or just start a new session — `plugin-bootstrap.js` compares the
-recorded state against the current plugin version on every `SessionStart` and
-rebuilds automatically if they differ.
-
-Then, whether or not a plugin update was just pulled, refresh the runtime
-against whatever `${CLAUDE_PLUGIN_ROOT}` currently resolves to. This stops the
-running dashboard server before starting the new one. Say so, then run:
+That downloads the new version into a NEW directory under
+`~/.claude/plugins/cache/`, while `${CLAUDE_PLUGIN_ROOT}` in this session still
+names the old one — and the old build's bootstrap refuses to run once a newer
+build is installed (`supersededBy`). So refresh the runtime from the build that
+is installed now: the new directory when one was just pulled, else this one.
+This stops the running dashboard server before starting the new one. Say so,
+then run:
 
 ```bash
-node "${CLAUDE_PLUGIN_ROOT}/scripts/plugin-bootstrap.js" --force
+ROOT=$(node -e 'console.log(require(process.argv[1]).supersededBy() || "")' \
+  "${CLAUDE_PLUGIN_ROOT}/scripts/plugin-bootstrap.js")
+ROOT="${ROOT:-${CLAUDE_PLUGIN_ROOT}}"
+echo "Refreshing the AgentHub runtime from $ROOT"
+node "$ROOT/scripts/plugin-bootstrap.js" --force
+node "$ROOT/scripts/plugin-doctor.js"
 ```
 
-It runs in the foreground and can take a few minutes on a cold cache. When it
-finishes, verify:
+Run it as ONE command (the shell does not keep `ROOT` between commands). The
+bootstrap runs in the foreground and can take a few minutes on a cold cache;
+the doctor that follows verifies the result.
 
-```bash
-node "${CLAUDE_PLUGIN_ROOT}/scripts/plugin-doctor.js"
-```
+If a new version was pulled, tell the user the dashboard already runs it, but
+this Claude Code session still loads the old plugin's commands and skills until
+they run `/reload-plugins` or start a new session.
 
 Report the final state in a few lines. If the bootstrap failed, quote the
-decisive line from `~/.claude/agenthub/runtime/bootstrap.log`.
+decisive line from `bootstrap.log` in the runtime dir (`<Data dir>/runtime` —
+the doctor's `Data dir` row; by default `~/.claude/agenthub/runtime`).