feat(module): add PlanForce to Module interface with stubs

internal/module/module.go

@@ -49,6 +49,12 @@ type Module interface {
 	Meta() Meta
 	Detect(ctx context.Context) (State, error)
 	Plan(ctx context.Context, current State) (Plan, error)
+	// PlanForce returns a plan that reapplies the module unconditionally,
+	// ignoring current detected state. Used by `archduino install --force`.
+	// Implementations should produce a plan equivalent to a from-scratch
+	// install — reinstall packages without pacman's --needed guard and
+	// rewrite managed config files.
+	PlanForce(ctx context.Context) (Plan, error)
 	Apply(ctx context.Context, plan Plan, r Reporter) error
 	Verify(ctx context.Context) error
 }

internal/module/registry_test.go

@@ -13,6 +13,7 @@ type fakeModule struct {
 func (f fakeModule) Meta() Meta                                  { return Meta{ID: f.id, Name: f.id, Deps: f.deps} }
 func (f fakeModule) Detect(context.Context) (State, error)       { return nil, nil }
 func (f fakeModule) Plan(context.Context, State) (Plan, error)   { return Plan{}, nil }
+func (f fakeModule) PlanForce(context.Context) (Plan, error)     { return Plan{}, nil }
 func (f fakeModule) Apply(context.Context, Plan, Reporter) error { return nil }
 func (f fakeModule) Verify(context.Context) error                { return nil }