issue 4531 slice 25: PublishingShell incremental queue item list #4787

Parent: #4531

Slice goal

PublishingShell site workspace shows the incremental queue as a list of items (content id and title or name), not only a count. Empty queue stays an empty state. H2 QA can prove the list against a site that has queued items.

Out of scope

Removing a queue item (sibling). Status job detail (sibling). Full/incremental publish buttons already shipped. #1371 UAT. JSF page deletes.

Acceptance criteria

• Queued items render as rows (id + label) for the selected site
• Empty queue does not show fake rows
• Load failure is visible
• Playwright surface-filtered spec on H2 QA
• product-docs/8.2 updated
• Update parent [8.2] Unified publishing — next React increments #4531 Agent progress section

Change class

One vertical increment (REST list only if the SPA cannot read items today, plus PublishingShell, Playwright, product-docs). Do not split layers.

H2 QA: perc-devctl qa-up → qa-health → TEST_CMS_URL → npm run test:surface → qa-down.

Leave unassigned. Do not add In Progress.

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