issue 4531 slice 44: PublishingShell copy a log item location #4937

Parent: #4531

Slice goal

From a PublishingShell log-detail row, the operator copies the published file location (file name or location) to the clipboard and sees a short confirmation. Empty locations do not claim success.

Out of scope

Downloading the file from the delivery server. Purging logs. Opening the editor (sibling slice).

Acceptance criteria

• Copy writes the location string and shows confirmation. Cancel/dismiss does not change logs.
• Missing location is named, not a silent success. Clipboard failure stays on the panel.
• Playwright surface spec (H2 QA mode, surface filter) plus product-docs note.
• Update parent [8.2] Unified publishing — next React increments #4531 Agent progress.

Change class

One vertical increment.

Leave unassigned. Do not add In Progress.

Co-Authored by Grok Build 1.0.41 using unspecified with agent night-issue-prs-triage.