…ius and alpha fixes

- adds a`morph` option to interactive dismiss: the
  destination view scales/translates with the finger, springs back on cancel,
  and morphs into the matching source element frame on finish (with
  shared-element snapshot fly-back).
- Gesture phase tracking (idle/pending/active/ignored) so vertical scrolls on
  inner scroll views no longer engage the dismiss; the inner scroll view is
  frozen while a dismiss is active.
- Adds `cornerRadius` to SharedProperties, animated across present/dismiss and
  driven by percent during interactive dismissal (sheet-style transitions).
- Uses native alpha instead of NS opacity when hiding shared elements during
  transitions, restoring from NS opacity as the source of truth. Tracks all
  presenting views (including duplicate sharedTransitionTags in sister lists)
  so cleanup restores every element and avoids double-image artifacts.
- Detaches imageSourceChange listeners on cleanup and seeds image snapshots
  from the source image to avoid a blank first frame.
- Disables iOS' built-in edge pan while a custom interactive dismiss is wired
  so it can't race the custom recognizer.
- snapshotView now restores layer opacity synchronously inside a CATransaction
  instead of on next tick, so cleanup opacity changes aren't clobbered.