Overflow issue on -K parameter

[Yoonsung1203]

Hello,

I tried adjusting the -K option in Winnowmap to increase memory usage and align more sequences per batch.
However, increasing this option led to an overflow issue, resulting in a situation where only one sequence was aligned per batch.

This appears to be caused by the mini_batch_size variable being declared as an int rather than int64_t in the code.
After modifying this, I confirmed that more sequences could be aligned per single batch.
(src/index.c, src/main.c, src/map.c, src/minimap.h)

I’m sharing this issue in case you’d consider applying a minor fix in a future update.