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

scripts/plugin-doctor.js

@@ -247,17 +247,48 @@ function systemdStatus() {
  * This checks the doctor's own PATH. A server started as a systemd `--user`
  * service can still see a different one — `GET /api/run/tmux` is the server's
  * own answer, and `agenthub doctor` reports that.
+ *
+ * Also WARN below tmux 3.7, the first with pane scrollbars (`tmux.js` turns
+ * them on), and when a new binary still talks to an older running server — a
+ * server keeps its version until every tmux session has closed. The doctor
+ * only says so: it never installs or restarts tmux.
  */
+const hasScrollbars = (version) => {
+  const m = /(\d+)\.(\d+)/.exec(version || "");
+  return !!m && (Number(m[1]) > 3 || (Number(m[1]) === 3 && Number(m[2]) >= 7));
+};
+
 function tmuxStatus() {
-  if (require("../server/lib/tmux").isTmuxAvailable()) {
-    return ["ok", "tmux", "on PATH — the run console can start sessions"];
+  const tmux = require("../server/lib/tmux");
+  const client = tmux.clientVersion();
+  if (!client) {
+    return [
+      "warn",
+      "tmux",
+      "not found — Start Run and `agenthub lanes shell` will fail (everything else is unaffected). " +
+        "Install it: sudo apt install tmux / brew install tmux (Windows: run AgentHub under WSL2)",
+    ];
   }
-  return [
-    "warn",
-    "tmux",
-    "not found — Start Run and `agenthub lanes shell` will fail (everything else is unaffected). " +
-      "Install it: sudo apt install tmux / brew install tmux (Windows: run AgentHub under WSL2)",
-  ];
+  if (!hasScrollbars(client)) {
+    return [
+      "warn",
+      "tmux",
+      `${client} works, but terminal panes get a scrollbar only from tmux 3.7. ` +
+        "Upgrade: brew upgrade tmux (macOS); on Linux, when the distro ships an older one " +
+        "(Ubuntu 24.04 has 3.4), build the release from https://github.com/tmux/tmux/releases " +
+        "(needs libevent-dev libncurses-dev bison: ./configure && make && sudo make install)",
+    ];
+  }
+  const server = tmux.serverVersion();
+  if (server && !hasScrollbars(server)) {
+    return [
+      "warn",
+      "tmux",
+      `${client} installed, but the running tmux server is ${server} — panes get their ` +
+        "scrollbar once every tmux session has closed (or after a reboot)",
+    ];
+  }
+  return ["ok", "tmux", `${client} on PATH — the run console can start sessions, with scrollbars`];
 }
 
 function countLegacyHookEntries() {