feat(cli): Support displaying storage values in base-2 [#2492] (#2502)

* Update display on repository summary

* Apply throughout app

* Situate units_test

* Update Command Line documentation

* Envar cleanup

* Rename to BytesString

* Restore envar string available for test

* Remove extraneous empty check and restore UIPreferences field for frontend

* PR: config bool cleanup and missed `BaseEnv`s

* Fix lint and test

cli/command_content_stats.go

@@ -48,7 +48,7 @@ func (c *commandContentStats) run(ctx context.Context, rep repo.DirectRepository
 		return errors.Wrap(err, "error calculating totals")
 	}
 
-	sizeToString := units.BytesStringBase10
+	sizeToString := units.BytesString
 	if c.raw {
 		sizeToString = func(l int64) string {
 			return strconv.FormatInt(l, 10) //nolint:gomnd