Add batch still arrows, hide output only on tap, and cut studio lag.

Co-authored-by: Cursor <cursoragent@cursor.com>

utils/libraryBrowse.ts

@@ -93,6 +93,17 @@ export function chronologicalStills(parts: LibraryStill[]) {
   })
 }
 
+export function stillsInFamily(stills: LibraryStill[], current?: LibraryStill | null) {
+  if (!current) return [] as LibraryStill[]
+  if (!current.familyId) return [current]
+  return chronologicalStills(stills.filter(item => item.familyId === current.familyId && item.role !== 'input'))
+}
+
+export function wrappedIndex(length: number, current: number, delta: number) {
+  if (length <= 0) return 0
+  return ((current + delta) % length + length) % length
+}
+
 export function sortClipParts(a: LibraryClip, b: LibraryClip) {
   const durationDelta = (Number(b.duration) || 0) - (Number(a.duration) || 0)
   if (durationDelta) return durationDelta