ws63-rust v1.96.0-1 (riscv32imfc hard-float)

Custom Rust toolchain for the HiSilicon WS63 (RISC-V RV32IMFC_Zicsr,
hard-float ilp32f, no atomics). The riscv32imfc-unknown-none-elf
target is builtin — downstream builds need no -Z build-std.

Install:

tar xzf ws63-rust-*-x86_64-unknown-linux-gnu.tar.gz
rustup toolchain link ws63 "$PWD/stage2"

Sysroot ships: rustc + cargo + rustfmt + clippy + rustdoc,
rust-analyzer-proc-macro-srv (LSP proc-macro expansion), rust-src,
llvm-tools (rust-objcopy …), rust-gdb / rust-lldb + pretty-printers,
and precompiled core/alloc for the target.