fix: event-loop freezes, plugin-install boot crash, tmux attach/scrollbar, Codex transcripts

- GET /api/workflows: one LEAD() window pass in a read worker (read-pool.js,
  workflow-stats.js); idx_events_session restored, idx_events_tool added
- compat-sqlite gains function/pluck/readonly so a plugin install without a
  better-sqlite3 build boots again; antigravity-usage uses db.js's Database
- install-hooks adds no checkout hooks while the agenthub plugin is enabled
  (events were doubled)
- terminal attach runs the live tmux server's own binary; the pane scrollbar
  gets a visible 2-column style, and claude panes start with
  CLAUDE_CODE_DISABLE_ALTERNATE_SCREEN=1 so tmux keeps history to scroll
- Codex sessions' conversation in GET /api/sessions/:id/transcript
- Codex/Antigravity sessions claimed by their workspace without hooks
- UI-audit follow-ups, docs and OpenAPI

INSTALL.md

@@ -31,7 +31,7 @@ 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 | **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 lanes 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` |
 | Python | 3.6+ | Optional — only for `scripts/expand-ts-module-docs.py` (doc generation) |
@@ -55,6 +55,19 @@ sudo pacman -S git tmux          # Arch
 Windows has no native tmux. Run AgentHub under **WSL2** and install it inside
 the WSL distro — a tmux from Git Bash or MSYS is not what the server executes.
 
+A terminal pane gets a draggable scrollbar only on **tmux 3.7+** — older
+versions work, just without it, and `/agenthub-doctor` warns. Homebrew ships the
+latest (`brew upgrade tmux`); Ubuntu 24.04's apt has 3.4, so build the release:
+
+```bash
+sudo apt install build-essential pkg-config libevent-dev libncurses-dev bison
+curl -fsSL https://github.com/tmux/tmux/releases/download/3.7c/tmux-3.7c.tar.gz | tar xz
+cd tmux-3.7c && ./configure && make && sudo make install   # into /usr/local/bin
+```
+
+A tmux server already running keeps its old version until every tmux session
+has closed (or the machine reboots) — only then do the scrollbars appear.
+
 Check it:
 
 ```bash
@@ -72,7 +85,8 @@ curl -s localhost:4820/api/run/tmux      # {"available":true}
 
 **No configuration is needed.** AgentHub creates its own session per lane,
 named `agenthub-lane-<id>`, and never reads your `~/.tmux.conf` for anything it
-depends on (mouse mode is set on the session explicitly). You can attach to the
+depends on (mouse mode, the hidden status bar and the scrollbar are set on the
+session explicitly). You can attach to the
 exact same pane from a normal terminal:
 
 ```bash
@@ -191,7 +205,7 @@ This starts two processes concurrently:
 Open **http://localhost:5173** in your browser.
 
 > [!TIP]
-> When you run the dashboard directly on the host with `npm run dev` or `npm start`, the server automatically writes the Claude Code hook configuration to `~/.claude/settings.json`. If you run the dashboard inside a container, install hooks from the host with `npm run install-hooks` instead — a hook path written from inside a container points at the container filesystem.
+> When you run the dashboard directly on the host with `npm run dev` or `npm start`, the server automatically writes the Claude Code hook configuration to `~/.claude/settings.json` — unless the `agenthub` plugin is enabled there, whose own hooks already run; then it removes any copies a checkout wrote instead, since two sets post every event twice. If you run the dashboard inside a container, install hooks from the host with `npm run install-hooks` instead — a hook path written from inside a container points at the container filesystem.
 
 ---