fix: make web updates restart cleanly

cmd/vocat/main.go

@@ -248,6 +248,10 @@ func run(logger *slog.Logger, logs *loghub.Hub) error {
 	case <-signalContext.Done():
 		logger.Info("shutdown signal received")
 	}
+	// Long-lived SSE and polling handlers use this context. Stop them before
+	// http.Server.Shutdown so they do not consume the entire graceful-shutdown
+	// deadline while waiting for a stream that is intentionally still active.
+	cancelPolling()
 
 	shutdownContext, cancelShutdown := context.WithTimeout(
 		context.Background(),

internal/update/update.go

@@ -232,7 +232,10 @@ func RestartService(logger *slog.Logger) error {
 	if _, err := exec.LookPath("systemctl"); err != nil {
 		return fmt.Errorf("systemctl not found in PATH")
 	}
-	cmd := exec.Command("systemctl", "restart", "vocat")
+	// Queue the restart and let systemctl exit before systemd stops this unit.
+	// A blocking restart command becomes part of vocat.service's own cgroup and
+	// waits for that same cgroup to terminate, creating a stop-timeout cycle.
+	cmd := exec.Command("systemctl", "restart", "--no-block", "vocat")
 	if out, err := cmd.CombinedOutput(); err != nil {
 		logger.Warn("systemctl restart failed", "error", err, "output", string(out))
 		return fmt.Errorf("systemctl restart vocat: %w", err)

scripts/install.sh

@@ -216,7 +216,9 @@ ExecStart=${BINARY_PATH}
 Restart=on-failure
 RestartSec=3s
 TimeoutStartSec=30s
-TimeoutStopSec=20s
+# HTTP, VoWiFi, and modem cleanup have bounded shutdown contexts totalling up
+# to 30 seconds. Leave a small margin before systemd resorts to SIGKILL.
+TimeoutStopSec=40s
 
 AmbientCapabilities=CAP_NET_ADMIN CAP_NET_RAW
 CapabilityBoundingSet=CAP_NET_ADMIN CAP_NET_RAW