issue 4531 slice 49: PublishingShell delete the open site #4976

Parent: #4531

Slice goal

PublishingShell site workspace: delete the open site after an explicit confirm. On success, leave the workspace and refresh the sites list so the deleted site is gone. Cancel does not call DELETE.

REST already exists: DELETE /services/sites/{nameOrId} (sitesApi.deleteSite). This slice is the PublishingShell vertical (UI + surface-filtered Playwright + product-docs). Do not split REST vs SPA vs Playwright into separate PRs.

Out of scope

• Rename (issue 4531 slice 47: PublishingShell rename the open site #4960) and copy (issue 4531 slice 48: PublishingShell copy the open site #4961), already shipped
• Description or base URL edits (sibling slices)
• Delivery-server delete
• JSF deep-page retirement (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 human UAT UAT sign-off for unified Publishing UI (SC-001 / SC-003 / SC-008) #1371

Acceptance criteria

• Confirm deletes the open site and the sites list no longer shows it
• Cancel does not delete
• HTTP 403/404/409 stay on the workspace and do not claim the site was deleted
• Vitest plus surface-filtered Playwright (perc-devctl qa-up → qa-health → TEST_CMS_URL → npm run test:surface → qa-down)
• product-docs/8.2 publishing page updated
• Update parent [8.2] Unified publishing — next React increments #4531 Agent progress when the PR opens

Leave unassigned. Do not add In Progress.

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