feat(packages): implement PlanForce to reinstall all packages

Adds Reinstall method to PackageManager and AURHelper interfaces
so modules can invoke the concrete Reinstall helpers behind the
interface. *Pacman and *Yay already satisfy it.

internal/modules/packages/packages.go

@@ -3,7 +3,6 @@ package packages
 
 import (
 	"context"
-	"errors"
 	"fmt"
 	"strings"
 
@@ -75,5 +74,13 @@ func (m Module) Verify(ctx context.Context) error {
 }
 
 func (m Module) PlanForce(ctx context.Context) (module.Plan, error) {
-	return module.Plan{}, errors.New("PlanForce not implemented")
+	if len(m.pkgs) == 0 {
+		return module.Plan{}, nil
+	}
+	pkgs := append([]string{}, m.pkgs...)
+	return module.Plan{Actions: []module.Action{{
+		Description: "pacman -S (force) " + strings.Join(pkgs, ", "),
+		Kind:        module.ActionPackageInstall,
+		Exec:        func(ctx context.Context) error { return m.pm.Reinstall(ctx, pkgs) },
+	}}}, nil
 }