issue 4531 slice 24: PublishingShell export filtered logs #4767

Parent: #4531

Slice goal

From PublishingShell Logs, an operator downloads the currently filtered log list (CSV or equivalent text file) including the visible columns. Empty filter result downloads a header-only file, not an error.

Out of scope

Status site filter (sibling). Open log item in editor (sibling). Log purge (shipped).

Acceptance criteria

• Download matches the filtered rows on screen
• Empty list still downloads headers; failure to build the file is visible
• Playwright surface-filtered spec
• product-docs/8.2
• Update parent [8.2] Unified publishing — next React increments #4531 Agent progress section

Change class

One vertical increment. 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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