Fixes#18556 by using RUSTC_WRAPPER instead of setting RUSTFLAGS directly.
This allows Homebrew's optimization flags to coexist with .cargo/config.toml
settings, preventing build failures when projects have their own Rust
configuration.
- Add rustc_wrapper shim that clears RUSTFLAGS and prepends HOMEBREW_RUSTFLAGS
- Update both std and super environments to use RUSTC_WRAPPER
- Store Homebrew's rustflags in HOMEBREW_RUSTFLAGS instead of RUSTFLAGS
🤖 Generated with [Claude Code](https://claude.ai/code)
Co-Authored-By: Claude <noreply@anthropic.com>
Co-authored-by: Carlo Cabrera <github@carlo.cab>
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