limit arithmetic literals are all ints but different types

[jennifersp]

for query with ... limit 0, 200 in TopN plan, arithmetic was returning decimal type because 200 was handled asuint8 and 0 was int8 types, so if the both the values are any non-matching int type, the values are converted to int64 for + and - operations.

[fulghum]

Looks good! 🚢