Consider custom linting for Rust API design guidelines

Description:
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Currently, enforcement of the Rust API design guidelines (e.g. preferring traits for public APIs) is handled through code review.
In the future, once our Rust toolchain and processes are finalized (possibly via an ADR), we could explore introducing automated linting.

Options to investigate:

- Clippy: no direct support for custom lints.

- dylint: possible framework for custom lint rules.

- Alternative approaches: rustdoc JSON checks, cargo-public-api, etc.

Next steps:
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Keep this issue in the backlog for reference.

Revisit once tooling decisions are finalized.