ecmult: Clean up integer types in _ecmult_wnaf #1795

1. 
   real-or-random commented at 2:20 pm on January 7, 2026: contributor

   Fixes #1769.

   On top of #1794.

2. real-or-random added the label tweak/refactor on Jan 7, 2026
3. ecmult: Clean up integer types in strauss 0f75e12a90
4. ecmult: Fix VERIFY_CHECK to exclude UB

   Left-shifting an int32_t by 31 may be signed overflow

   242df7f18a
5. real-or-random force-pushed on Jan 7, 2026
6. 
   hebasto commented at 2:49 pm on January 7, 2026: member

   Concept ACK.

Contributors
real-or-random hebasto

Labels
tweak/refactor