feat(install): auto-start the dashboard on boot via systemd, no Claude Code needed

Adds ccam service install/uninstall/status for checkout installs and wires
the same systemd --user unit into plugin-bootstrap.js, so plugin-installed
colleagues get boot persistence too instead of needing a Claude Code
session to (re)start the server after every reboot.

scripts/systemd-service.js

@@ -0,0 +1,117 @@
+#!/usr/bin/env node
+/**
+ * @file systemd-service.js
+ * @description Shared helper for installing/removing a systemd `--user`
+ * service that keeps the CCAM dashboard server running across reboots,
+ * without needing Claude Code (or any other tool) to be started first.
+ * Used by both `ccam service install` (checkout installs) and
+ * `plugin-bootstrap.js` (plugin installs) so the two paths stay in sync.
+ * Linux/systemd only — callers fall back to their existing manual-start
+ * path when `systemctlAvailable()` is false.
+ * @author Nguyễn Ngọc Trí Vĩ <vinnt@smartgift.vn>
+ */
+
+const fs = require("fs");
+const os = require("os");
+const path = require("path");
+const { spawnSync } = require("child_process");
+
+const MARKER = "# ccam-managed-unit — regenerated on install, do not edit by hand";
+
+function unitDir() {
+  return path.join(os.homedir(), ".config", "systemd", "user");
+}
+
+function unitPath(name) {
+  return path.join(unitDir(), `${name}.service`);
+}
+
+function systemctlAvailable() {
+  if (process.platform !== "linux") return false;
+  return spawnSync("systemctl", ["--user", "--version"], { stdio: "ignore" }).status === 0;
+}
+
+function unitContent({ description, workingDir, execStart, env }) {
+  const envLines = Object.entries(env)
+    .map(([k, v]) => `Environment=${k}=${v}`)
+    .join("\n");
+  return `[Unit]
+${MARKER}
+Description=${description}
+After=network.target
+
+[Service]
+Type=simple
+WorkingDirectory=${workingDir}
+ExecStart=${execStart}
+Restart=on-failure
+RestartSec=3
+${envLines}
+
+[Install]
+WantedBy=default.target
+`;
+}
+
+function systemctl(args) {
+  return spawnSync("systemctl", ["--user", ...args], { stdio: "inherit" });
+}
+
+/**
+ * Writes (or refreshes) the unit file and enables + starts it. Idempotent:
+ * an unchanged unit is left running as-is; a changed one (e.g. a plugin
+ * cache path after an update) is reloaded and restarted.
+ *
+ * @returns {"written"|"unchanged"|"foreign"|"unavailable"|"failed"}
+ */
+function installUserService({ name, description, workingDir, execStart, env = {} }) {
+  if (!systemctlAvailable()) return "unavailable";
+  const body = unitContent({ description, workingDir, execStart, env });
+  const target = unitPath(name);
+  try {
+    if (fs.existsSync(target)) {
+      const current = fs.readFileSync(target, "utf8");
+      if (!current.includes(MARKER)) return "foreign";
+      if (current === body) {
+        systemctl(["enable", "--now", `${name}.service`]);
+        return "unchanged";
+      }
+    }
+    fs.mkdirSync(unitDir(), { recursive: true });
+    fs.writeFileSync(target, body, "utf8");
+    systemctl(["daemon-reload"]);
+    systemctl(["enable", "--now", `${name}.service`]);
+    systemctl(["restart", `${name}.service`]);
+    return "written";
+  } catch {
+    return "failed";
+  }
+}
+
+/** @returns {"removed"|"absent"|"foreign"|"unavailable"} */
+function uninstallUserService(name) {
+  if (!systemctlAvailable()) return "unavailable";
+  const target = unitPath(name);
+  if (!fs.existsSync(target)) return "absent";
+  if (!fs.readFileSync(target, "utf8").includes(MARKER)) return "foreign";
+  systemctl(["disable", "--now", `${name}.service`]);
+  fs.rmSync(target, { force: true });
+  systemctl(["daemon-reload"]);
+  return "removed";
+}
+
+/** Lets the user service start on cold boot, not just after login. Best
+ *  effort — some setups require an admin to grant this, so a failure here
+ *  is reported, never thrown. */
+function enableLinger() {
+  const user = os.userInfo().username;
+  return spawnSync("loginctl", ["enable-linger", user], { stdio: "ignore" }).status === 0;
+}
+
+module.exports = {
+  systemctlAvailable,
+  installUserService,
+  uninstallUserService,
+  enableLinger,
+  unitPath,
+};