v0.8.19: Stats-aware scanning, faster GPU index training, and prefiltering bug fixes

New Features

• feat: a tensor dataset that shared with the same behavior as Lance torch Dataset by @eddyxu in #1679
• feat: add option to pass in precomputed row_id -> ivf partiton mapping and compute partiiton on GPU by @chebbyChefNEQ in #1680
• feat: add batch buffering and async loading to torch.LanceDataset by @chebbyChefNEQ in #1687
• feat: optimized pushdown scanner by @wjones127 in #1328

Bug Fixes

• fix: dont use scalar indices unless we are prefiltering by @westonpace in #1678
• fix: lance pytorch dataset parameter to load with row_id by @eddyxu in #1676
• fix: make sure to prefilter the flat portion of a combined knn by @westonpace in #1583

Performance Improvements

• perf: use datafusion to shuffle index partition data by @wjones127 in #1645

Other Changes

• chore: add utility to compute ground truth for benchmarks by @eddyxu in #1668
• chore: add new python benchmarks for testing scalar indices by @westonpace in #1658

Full Changelog: v0.8.18...v0.8.19