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/repo_remove.go

@@ -54,7 +54,7 @@ func aptlyRepoRemove(cmd *commander.Command, args []string) error {
 		return fmt.Errorf("unable to remove: %s", err)
 	}
 
-	toRemove.ForEach(func(p *deb.Package) error {
+	_ = toRemove.ForEach(func(p *deb.Package) error {
 		list.Remove(p)
 		context.Progress().ColoredPrintf("@r[-]@| %s removed", p)
 		return nil