resizeForCapacity method
Grows the nid-indexed sticky array to match the controller's current nid capacity. Called from the render object's layout-array growth path so all per-nid arrays stay in lockstep.
Implementation
void resizeForCapacity(int nidCapacity) {
if (nidCapacity <= _stickyByNid.length) return;
final newSticky = List<StickyHeaderInfo<TKey>?>.filled(nidCapacity, null);
for (int i = 0; i < _stickyByNid.length; i++) {
newSticky[i] = _stickyByNid[i];
}
_stickyByNid = newSticky;
}