Merge branch 'tn/stash-avoid-sparse-index-expansion' into jch

The 'git stash push' command has been optimized to avoid unnecessary sparse index expansion when pathspecs are wholly inside the sparse-checkout cone. Also, a potential out-of-bounds read in the sparse-index expansion check helper pathspec_needs_expanded_index() has been fixed by consistently using the parsed, prefixed path. * tn/stash-avoid-sparse-index-expansion: stash: avoid sparse-index expansion for in-cone paths pathspec: use match for sparse-index expansion checks