GH-32381: [C++] Improve error handling for hash table merges#49512

kris-gaudel wants to merge 3 commits intoapache:mainapache/arrow:mainfrom

kris-gaudel:kris-gaudel/hash-table-merge-errorskris-gaudel/arrow:kris-gaudel/hash-table-merge-errorsCopy head branch name to clipboard