Remove the dedicated Carrier Type accordion step and merge the
Image/Audio toggle into the Carrier & Mode step. The toggle now sits
in a two-column row aligned with the embedding mode buttons. Steps
renumbered from 4 to 3, carrier label changed to "Carrier File",
mode hint updates on carrier type switch via dispatched change events.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>