User asked for the chevron to be on the left of the playlist input,
not tucked after the quality selector on the right.
- Remove chevron from qualityEl (it was between the quality select and
the remove button)
- Add it as the first child of capture-row-main, before the <input>,
when isPlaylistSource && playlistProbeState === 'done'
- Show a same-width placeholder span while probing/idle/error so the
input does not jump left when the chevron appears after probe completes
- Add capture-playlist-toggle--left modifier (flex-shrink:0, tighter
padding) and .capture-playlist-toggle-placeholder (fixed 22px width)
Previous text said 'using best quality' implying the capture would
proceed, but probe error now blocks submission. Replace with 'Probe
failed — edit URL to retry' in orange (capture-quality-hint--error)
so the disabled button and the message are consistent.