feat: manage task process lifetimes and preserve turn history

internal/security/procattr_windows.go

@@ -3,9 +3,11 @@
 package security
 
 import (
+	"context"
 	"os/exec"
 	"strconv"
 	"syscall"
+	"time"
 )
 
 func prepareShellCmdSession(cmd *exec.Cmd) error {
@@ -29,7 +31,9 @@ func terminateProcessGroup(rootPID int, cmd *exec.Cmd) {
 	if pid <= 0 {
 		return
 	}
-	tk := exec.Command("taskkill", "/F", "/T", "/PID", strconv.Itoa(pid))
+	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+	defer cancel()
+	tk := exec.CommandContext(ctx, "taskkill", "/F", "/T", "/PID", strconv.Itoa(pid))
 	if err := tk.Run(); err != nil {
 		if cmd != nil && cmd.Process != nil {
 			_ = cmd.Process.Kill()
@@ -41,3 +45,12 @@ func terminateProcessGroup(rootPID int, cmd *exec.Cmd) {
 func terminateCmdTree(cmd *exec.Cmd) {
 	terminateProcessGroup(0, cmd)
 }
+
+func stopProcessGroup(pid int, cmd *exec.Cmd) {
+	// Windows has no portable SIGTERM equivalent for arbitrary console jobs.
+	terminateProcessGroup(pid, cmd)
+}
+
+// Windows taskkill /T is best effort; unlike a Unix PGID it has no persistent
+// group handle to query after the root exits. Job Objects are needed for that.
+func processGroupExists(pid int) bool { return false }