This commit introduces a new `ecmultWindowedVar` function that implements optimized windowed multiplication for scalar multiplication, significantly improving performance during verification operations. The existing `Ecmult` function is updated to utilize this new implementation, converting points to affine coordinates for efficiency. Additionally, the `EcmultConst` function is retained for constant-time operations. The changes also include enhancements to the generator multiplication context, utilizing precomputed byte points for improved efficiency. Overall, these optimizations lead to a notable reduction in operation times for cryptographic computations.
This commit introduces a new test file for context management, covering various scenarios for context creation, destruction, and capabilities. Additionally, it implements the generator multiplication context, enhancing the secp256k1 elliptic curve operations. The changes ensure comprehensive testing and improved functionality for context handling, contributing to the overall robustness of the implementation.
