Motivation:

1. We can get rid of lazy_static! in favor of std::sync::LazyLock
2. We can use {integer}::div_ceil
   

   frost/frost-core/src/scalar_mul.rs

   Line 28 in ca33dad

   const fn div_ceil(lhs: usize, rhs: usize) -> usize {

3. Crates from RustCrypto already have pre-releases that require Rust 1.73+ or even Rust 1.81+ in some cases. For example: https://github.com/RustCrypto/elliptic-curves/blob/master/k256/Cargo.toml
4. Starting with 1.81 we can use core::error::Error and remove the thiserror-nostd-notrait dependency in favor of thiserror: Allow disabling std dependency on 1.81+ dtolnay/thiserror#373