add clippy flags (#301)

## Type

- [ ] feature
- [ ] bugfix
- [ ] dev (no functional changes, no API changes)
- [ ] fmt (formatting, renaming)
- [ ] build
- [ ] docs
- [ ] testing

## Description


## Breaking changes?

- [ ] yes
- [ ] no

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Author: nitsan-starkware

.github/workflows/check.yml

@@ -25,7 +25,7 @@ jobs:
       - run: rustup toolchain install nightly-2025-07-14 --profile minimal
       - run: rustup component add clippy --toolchain nightly-2025-07-14
       - uses: Swatinem/rust-cache@v2
-      - run: cargo +nightly-2025-07-14 clippy --workspace --all-targets --all-features -- -D warnings -D future-incompatible -D rust-2018-idioms
+      - run: cargo +nightly-2025-07-14 clippy --workspace --all-targets --all-features -- -D warnings -D future-incompatible -D nonstandard-style -D rust-2018-idioms -D unused
 
   tests:
     runs-on: namespace-profile-starkware-libs-proving-utils-large-ubuntu-24-04-amd64