Try to use a parameter for the workspaces toolbar destination link

Problem/Motivation

See https://git.drupalcode.org/project/drupal/-/merge_requests/9116/diffs#no... for discussion.

The workspaces navigation integration currently sets max-age 0. This is because of the destination URL parameter.

Core's CSRF token generation handling uses a placeholder/lazy builder for only the csrf token - maybe we can use the same approach, then everything else could be cacheable and only the destination would be generated every request.

See RouteProcessorCsrf for the implementation.

Steps to reproduce

Proposed resolution

Remaining tasks

User interface changes

Introduced terminology

API changes

Data model changes

Release notes snippet