New ActiveDownloadsPanel pinned at the top of the Downloads tab shows what's
running (pulsing dot + live mm:ss timer counting from started_at) and what's
queued, so the operator can see activity at a glance without the running
filter. Backed by store.loadActive() which fetches running + pending
independent of the feed filter; refreshed every 4s by the existing live poll.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
