Replace the duplicated per-platform segment-skip logic with a shared
useMediaSegments hook: per-type skippers, overlap priority
(Commercial > Recap > Intro > Preview > Outro) and a single auto-skip
driver so both platforms behave identically.
- One auto-skip effect on the priority-resolved active segment, so
overlapping auto segments can't fire competing seeks.
- Sub-second precision (stop flooring currentTime to whole seconds).
- Gate auto-skip on !isBuffering plus a short arm delay so it never
seeks a not-yet-seekable transcoded stream at a 0:00 intro.
- Dedup guard survives the transient null when a transcoded stream
bounces the reported position, instead of looping seeks.
