feat: prompt for confirmation on storage:destroy

`storage:destroy` now prompts for confirmation before removing a named storage entry, matching the behavior of other destructive commands such as `apps:destroy` and `network:destroy`. The prompt can be skipped with the `--force` flag or the global `dokku --force` flag for non-interactive callers.

plugins/storage/src/commands/commands.go

@@ -19,7 +19,7 @@ Additional commands:`
 
 	helpContent = `
     storage:create <name> [<path>] [flags], Register a named storage entry
-    storage:destroy <name>, Remove a named storage entry (must be unmounted from every app first)
+    storage:destroy <name> [--force], Remove a named storage entry (must be unmounted from every app first)
     storage:ensure-directory [--chown option] <directory>, [DEPRECATED] use storage:create instead
     storage:exec <name> [-- <cmd>...], Run a command (or shell) in a temporary container that mounts the entry
     storage:info <name> [--format text|json], Show details for one storage entry

plugins/storage/src/subcommands/subcommands.go

@@ -58,8 +58,9 @@ func main() {
 		})
 	case "destroy":
 		args := flag.NewFlagSet("storage:destroy", flag.ExitOnError)
+		force := args.Bool("force", false, "--force: force destroy without confirmation")
 		args.Parse(os.Args[2:])
-		err = storage.CommandDestroy(args.Arg(0))
+		err = storage.CommandDestroy(args.Arg(0), *force)
 	case "ensure-directory":
 		args := flag.NewFlagSet("storage:ensure-directory", flag.ExitOnError)
 		chown := args.String("chown", "herokuish", "--chown: chown option (herokuish, heroku, paketo, root, false)")