issue 4531 slice 4: PublishingShell publish now #4579

Parent

Parent: #4531

After history (#4536), schedule dates (#4537), and site-workspace takedown (#4538). Remaining jQuery: publish now on page/resource (PercItemPublisherService / ITM-01).

Slice goal

One user-visible increment: An Admin can publish now a selected page or resource from PublishingShell site workspace (not Explorer, not jQuery finder); Playwright + product-docs.

HARD BAN: do not split REST vs SPA vs Playwright. Do not implement stage/unstage or publishing-actions menu in this PR.

In scope

1. Reuse existing /sitemanage/publish/page/{id} and /sitemanage/publish/resource/{id} (or current item-publish peers) from PublishingShell site workspace selection.
2. Confirm dialog; map 400/403/404; refresh workspace list/status.
3. Surface-filtered Playwright on QA H2 (perc-devctl qa-up → TEST_CMS_URL → test:surface).
4. Update product-docs/8.2/ publishing admin pages.

Out of scope

• Stage / unstage (slice 5)
• Get publishing actions menu (slice 6)
• JSF deletes (issue 1372 slice 3: Delete Runtime deep JSF pages under ui/pubruntime (keep index redirect) #1818/issue 1372 slice 2: Delete Design deep JSF pages under ui/publishing (keep index redirect) #1819) and qa-task UAT sign-off for unified Publishing UI (SC-001 / SC-003 / SC-008) #1371
• Full/incremental site publish (already shipped)

Acceptance

• Admin can publish now a selected page and a resource from PublishingShell site workspace
• Non-Admin 403; unknown id 404; validation 400 shown, not silent
• Playwright surface spec green on QA H2
• Product-docs match shipped behavior; [8.2] Unified publishing — next React increments #4531 Agent progress updated

Modules

WebUI, modules/perc-qa-automation, product-docs/8.2/ (REST/sitemanage only if a companion is missing)

Leave unassigned. Do not add In Progress.

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