Add read-only server endpoints for yeeke return packages (paginated list with order/tracking/shop/item/variation/claim-status/create-time filters, plus package detail with items) and extend the existing sync-runs endpoint with trigger/status/started-at filters, backward compatible. Split the admin menu into two modules per the ticket's confirmed scope adjustment: yeeke_returns (packages) and the new yeeke_sync_runs, both under the 采集采购 menu group, wired via a new sys_menu migration mirroring #237's precedent. Add the corresponding Vue pages, API wrappers and Go tests. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com> Claude-Session: https://claude.ai/code/session_01NTDbDcwbDw1TSAcE6wfh2F