issue 4531 slice 14: PublishingShell design content-list save #4676

Parent: #4531

Slice goal

PublishingShell Design: save content list (ContentListEditor). Operator edits a content list and saves; 403/409 mapped.

Out of scope

Edition save (slice 10). Delivery types (sibling).

Acceptance criteria

• Save content list from Design; dirty form + success/error
• Playwright surface-filtered spec
• product-docs/8.2
• Update parent [8.2] Unified publishing — next React increments #4531 Agent progress

Change class

One vertical increment.

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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