clawmates-node: host terminal uses tmux (resumable, redraw-on-attach)

The node terminal opened a bare bash PTY — bash prints its prompt once, so a
freshly-attached xterm showed nothing. Switch to `tmux new-session -A -s
clawmates` on the HOST (mirrors the agent terminal, but on the node itself, not
in a container): tmux redraws the whole screen on attach (no blank), and the
session is resumable across reopens. Starts in $HOME. Falls back to a login
shell if tmux is unavailable. ensure_tmux() best-effort installs tmux via the
host package manager when the daemon runs as root (systemd); otherwise logs a
hint to `apt install tmux`. Rebuilt + re-hosted both binaries.

Co-Authored-By: Claude Opus 4.8 (1M context) <[email protected]>

crates/bins/clawmates-node/src/main.rs

@@ -43,6 +43,7 @@ async fn main() {
         std::process::exit(2);
     }
     tailscale_up(&ts_authkey);
+    ensure_tmux();
     let ws_url = ws_url(&server, &token);
     println!("clawmates-node {VERSION} connecting to {server}");
     loop {
@@ -277,9 +278,26 @@ async fn open_pty(
     let pair = native_pty_system()
         .openpty(PtySize { rows, cols, pixel_width: 0, pixel_height: 0 })
         .map_err(|e| e.to_string())?;
-    let shell = std::env::var("SHELL").unwrap_or_else(|_| "/bin/bash".to_owned());
+    // Prefer a resumable host tmux session (like the agent terminal): `-A` attaches
-    let mut cmd = CommandBuilder::new(shell);
+    // to the existing "clawmates" session or creates it, and tmux redraws the whole
+    // screen on attach (so the view is never blank). Fall back to a login shell.
+    let mut cmd = if has_tmux() {
+        let mut c = CommandBuilder::new("tmux");
+        c.arg("new-session");
+        c.arg("-A");
+        c.arg("-s");
+        c.arg("clawmates");
+        c
+    } else {
+        let shell = std::env::var("SHELL").unwrap_or_else(|_| "/bin/bash".to_owned());
+        let mut c = CommandBuilder::new(shell);
+        c.arg("-l");
+        c
+    };
     cmd.env("TERM", "xterm-256color");
+    if let Ok(home) = std::env::var("HOME") {
+        cmd.cwd(home);
+    }
     let child = pair.slave.spawn_command(cmd).map_err(|e| e.to_string())?;
     drop(pair.slave);
     let mut reader = pair.master.try_clone_reader().map_err(|e| e.to_string())?;
@@ -439,3 +457,56 @@ fn tailscale_up(authkey: &str) {
         ])
         .status();
 }
+
+/// Is tmux on PATH?
+fn has_tmux() -> bool {
+    std::process::Command::new("tmux")
+        .arg("-V")
+        .output()
+        .map(|o| o.status.success())
+        .unwrap_or(false)
+}
+
+/// Best-effort: install tmux via the host package manager (works when the daemon
+/// runs as root, e.g. systemd). Non-interactive; if it can't, host terminals fall
+/// back to a plain login shell.
+fn ensure_tmux() {
+    if has_tmux() {
+        return;
+    }
+    let mgrs: &[(&str, &[&str])] = &[
+        ("apt-get", &["install", "-y", "tmux"]),
+        ("dnf", &["install", "-y", "tmux"]),
+        ("yum", &["install", "-y", "tmux"]),
+        ("apk", &["add", "--no-cache", "tmux"]),
+        ("pacman", &["-S", "--noconfirm", "tmux"]),
+        ("brew", &["install", "tmux"]),
+    ];
+    for (mgr, args) in mgrs {
+        let present = std::process::Command::new("sh")
+            .arg("-c")
+            .arg(format!("command -v {mgr}"))
+            .output()
+            .map(|o| o.status.success())
+            .unwrap_or(false);
+        if !present {
+            continue;
+        }
+        if *mgr == "apt-get" {
+            let _ = std::process::Command::new("apt-get")
+                .arg("update")
+                .env("DEBIAN_FRONTEND", "noninteractive")
+                .output();
+        }
+        let _ = std::process::Command::new(mgr)
+            .args(*args)
+            .env("DEBIAN_FRONTEND", "noninteractive")
+            .output();
+        break;
+    }
+    if has_tmux() {
+        println!("tmux ready for host terminals");
+    } else {
+        eprintln!("tmux not found (auto-install unavailable) — host terminal will use a plain shell; `apt install tmux` for resumable sessions");
+    }
+}