fix: #3626339 Show the Drupal messages and repair the back-office screens

Fixes the back-office problems a full browser round found in 4.0.0, and adds webship-js coverage of every back-office workflow.

Issue: https://www.drupal.org/project/uikit_admin/issues/3626339

Fixes (67 found, grouped)

• Status, warning and error messages print their text again (alert component takes the message).
• HTMX navigation no longer leaks ajax_page_state into form actions, links and redirects; excluded screens (batch, update check, tokens) keep full loads; behaviors and focus after a swap.
• Form items carry js-form-item, js-form-type-* and js-form-item-*: machine names, #states, the password check and contrib scripts (the Ace editor of Gherkin) work again.
• Dialog links (Create a new field, Place block, Delete operations) open their dialogs; Views UI dialogs show their forms; jQuery UI dialogs, vertical tabs, the pager, sticky table headers, search inputs, button links, error states and required markers are styled.
• Local tasks on node edit and revisions, tab order by weight, status counters linking to their groups, accent and focus colours applied, theme settings only on this theme's form, palette focus return.
• A visible Log out link in the rail, and the page varies per user (the rail names the person signed in).
• Requires Drupal core ^11.4.8 || ^12: with Twig 3.30, older 11.4 releases fail with an escape TypeError (https://www.drupal.org/i/3625969).

Tests

• 110 webship-js scenarios / 3071 steps: content, people, Views, blocks, structure, configuration, reports, HTMX page state, dialogs, core parts; every scenario checks no error was logged.
• Green locally on a CI-identical site (standard + page_content_type, webmaster) and on the dev site.
• CI: the drush-www wrapper uses runuser, so every argument reaches Drush intact.

AI-Generated: Yes

Checkpoints

• File an issue
• Fix
• Automated functional testing coverage
• Accessibility
• CI pipeline green
• Release