feat(17-04): menu:import-winter with the D-05 type map and read-only export SQL

- link to url, blog_categories to all-journal-categories, --map old=new on top; page entries dropped
- entries of unknown types or stale registry references dropped with their subtree, one report line per dropped or remapped entry
- ids, menu_id, parent_id, nest columns and sort_order kept; setval for both tables; --force, --dry-run, empty files copy nothing
- scripts/winter-export-menus.sql and winter-export-entries.sql
- TestMenuImportSmoke

plugin.go

@@ -5,9 +5,11 @@
 package menu
 
 import (
+	"git.golem15.com/golem15/sm-menu-plugin/console"
 	"git.golem15.com/golem15/sm-menu-plugin/models"
 	"git.golem15.com/golem15/sm-menu-plugin/updates"
 	"git.golem15.com/golem15/summercms/modules/backpack"
+	"git.golem15.com/golem15/summercms/modules/bonfire"
 	"git.golem15.com/golem15/summercms/modules/pact"
 	"git.golem15.com/golem15/summercms/modules/party"
 	"github.com/go-gormigrate/gormigrate/v2"
@@ -17,6 +19,7 @@ var (
 	_ party.Plugin       = (*Plugin)(nil)
 	_ pact.HasMigrations = (*Plugin)(nil)
 	_ pact.HasModels     = (*Plugin)(nil)
+	_ pact.HasCommands   = (*Plugin)(nil)
 )
 
 // Plugin is the golem15.menu plugin.
@@ -40,6 +43,11 @@ func (p *Plugin) Boot(app *backpack.App) error {
 	return nil
 }
 
+// Commands registers menu:import-winter.
+func (p *Plugin) Commands() []bonfire.Command {
+	return []bonfire.Command{console.ImportWinter(p.app)}
+}
+
 func (p *Plugin) Migrations() []*gormigrate.Migration { return updates.All() }
 
 func (p *Plugin) Models() []any { return models.All() }