go1.24: fix lint, unit and system tests

- development env: base on debian trixie with go1.24
- lint: run with default config
- fix lint errors
- fix unit tests
- fix system test

cmd/db.go

@@ -4,13 +4,13 @@ import (
 	"github.com/smira/commander"
 )
 
-func makeCmdDb() *commander.Command {
+func makeCmdDB() *commander.Command {
 	return &commander.Command{
 		UsageLine: "db",
 		Short:     "manage aptly's internal database and package pool",
 		Subcommands: []*commander.Command{
-			makeCmdDbCleanup(),
-			makeCmdDbRecover(),
+			makeCmdDBCleanup(),
+			makeCmdDBRecover(),
 		},
 	}
 }