fix(pat-structure): Fix ordering logic.

[thet]

The logic to set orderable columns in the structure pattern was quite wrong:

• The very first and second-to-last columns were set to no ordering. This PR fixes it to the very first (selection checkboxes) and very last column (actions column).

• The very first column was set for a default, ascending ordering. This went unnoticed, as the checkbox cells all have the same order information. This PR sets no initial ordering, as we want the order position in the container set as the default ordering.

Fixes: #1551

Now:

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Closes #

[petschki]

/run-coredev-robottests

[petschki]

hm ... somehow I have the feeling my coredev-robottests workflow doesn't use our checkedout plone.staticresources (see https://github.com/plone/mockup/actions/runs/22912898220/job/66490022037#step:13:44) ... need to look that up.

but for this one LGTM!