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

server/lib/pty-attach.js

@@ -1,7 +1,8 @@
 /**
  * @file pty-attach.js
  * @description Bridges one WebSocket connection to an `@lydell/node-pty`-backed
- * `tmux attach-session` process. Binary WS frames carry raw PTY bytes in
+ * `tmux attach-session` process, run with the live tmux server's own binary
+ * (`attachBinary`). Binary WS frames carry raw PTY bytes in
  * both directions; text WS frames carry small JSON control messages
  * (`resize`, and an outbound `exit` sent once when the pane process/tmux
  * session ends). Multiple browser tabs each get their own PTY attach
@@ -10,6 +11,7 @@
  * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
  */
 
+const fs = require("fs");
 const tmux = require("./tmux");
 
 const RUN_ID_RE = /^agenthub-lane-\d+(?:-[1-3])?$/;
@@ -34,6 +36,26 @@ function __setSpawnImpl(fn) {
   spawnImpl = fn;
 }
 
+/**
+ * The binary to run `tmux attach` with: the RUNNING server's own executable
+ * (`/proc/<pid>/exe`, which still works after a package upgrade replaced the
+ * file), else `tmux` on PATH. A client must match its server — tmux installed
+ * in a newer version while the server runs makes PATH's client fail every
+ * attach with "open terminal failed: not a terminal", though every other tmux
+ * command still works. Linux only; elsewhere PATH's tmux as before.
+ */
+function attachBinary() {
+  const pid = tmux.serverPid();
+  if (!pid) return "tmux";
+  const exe = `/proc/${pid}/exe`;
+  try {
+    fs.accessSync(exe, fs.constants.X_OK);
+    return exe;
+  } catch {
+    return "tmux";
+  }
+}
+
 /**
  * Attach `ws` to the tmux session `runId`. Spawns one PTY-backed
  * `tmux attach-session -t <runId>` per call.
@@ -48,7 +70,7 @@ function attach(ws, runId, { cols, rows }) {
   } catch {
     /* session gone or tmux unavailable — attach below will surface that */
   }
-  const pty = spawnImpl("tmux", ["attach-session", "-t", `=${runId}`], {
+  const pty = spawnImpl(attachBinary(), ["attach-session", "-t", `=${runId}`], {
     name: "xterm-256color",
     cols: cols || 80,
     rows: rows || 24,