To make Rust formatting consistent with the codebase this file adds tab spacing and maximum width rules for the Rust formatting `cargo fmt`.
We are placing the `.rustfmt.toml` file at the root of the project. According [[ https://github.com/rust-lang/rustfmt#configuring-rustfmt | to the documentation ]], we can use the project-wide file at the root of the project (parent directory).
The `rustfmt.toml` files form the sub-directories (services/commtest, services/identity, native/cpp/CommonCpp/CryptoTools/opaque-ke-cxx) were removed.
Linear task: [[ https://linear.app/comm/issue/ENG-1330/rust-notification-library-integration | ENG-1330 ]]