refactor: split ServiceCommand methods into dedicated files

- Move ServiceCommand.Start to commands_service_start.go
- Move ServiceCommand.Stop to commands_service_stop.go
- Move ServiceCommand.Restart to commands_service_restart.go
- Move ServiceCommand.Reload to commands_service_reload.go
- Move ServiceCommand.Status to commands_service_status.go
- Move ServiceCommand.Uninstall to commands_service_uninstall.go
- Move createStartCommands to commands_service_start.go
- Clean up imports in commands_service.go
- Remove all method implementations from main service file

This refactoring improves code organization by:
- Separating concerns into focused files
- Making navigation easier for developers
- Reducing merge conflicts between different commands
- Following consistent modular patterns
- Reducing commands_service.go from ~650 lines to ~50 lines

Each method is now co-located with its related functionality,
making the codebase more maintainable and easier to understand.

cmd/cli/commands_service_stop.go

@@ -0,0 +1,43 @@
+package cli
+
+import (
+	"errors"
+	"os"
+
+	"github.com/kardianos/service"
+	"github.com/spf13/cobra"
+)
+
+// Stop implements the logic from cmdStop.Run
+func (sc *ServiceCommand) Stop(cmd *cobra.Command, args []string) error {
+	s := sc.serviceManager.svc
+	p := sc.serviceManager.prog
+	readConfig(false)
+	v.Unmarshal(&cfg)
+	p.cfg = &cfg
+	p.preRun()
+	if ir := runningIface(s); ir != nil {
+		p.runningIface = ir.Name
+		p.requiredMultiNICsConfig = ir.All
+	}
+
+	initInteractiveLogging()
+
+	status, err := s.Status()
+	if errors.Is(err, service.ErrNotInstalled) {
+		mainLog.Load().Warn().Msg("service not installed")
+		return nil
+	}
+	if status == service.StatusStopped {
+		mainLog.Load().Warn().Msg("service is already stopped")
+		return nil
+	}
+
+	if err := checkDeactivationPin(s, nil); isCheckDeactivationPinErr(err) {
+		os.Exit(deactivationPinInvalidExitCode)
+	}
+	if doTasks([]task{{s.Stop, true, "Stop"}}) {
+		mainLog.Load().Notice().Msg("Service stopped")
+	}
+	return nil
+}