Supports Rust in opt-in Windows cross builds: Windows Rust tools run locally, Linux tools can use RBE, and Cargo selects pinned native MSVC while preserving declared Rust linker paths.

Container links safely materialize Rust standard-library archives, preserve linker options and quoted paths, enforce repository confinement, serialize creation, publish copies atomically, and clean temporary response files. Regenerates rules_rust 0.69.0 patches and refreshes the lockfile.

Extracted from #63670 after #64688; preserves C++ execution policy.

Validation: 40 focused tests and the strict lockfile check pass after rebase. Native Windows/macOS CI and clean-configuration lint passed before rebase.