openai/gpt-5.2-chat → B (4:1)

Side B pins `rustfmt` and `clippy` in `rust-toolchain.toml`, adds VS Code settings to enforce the project toolchain, and standardizes formatting across the workspace—improving reproducibility and developer experience long-term. Side A mostly removes small UI elements (e.g., deleting the vote scope paragraph and back-nav function) and tweaks CSS gradients, which are comparatively minor and cosmetic.