0.11.11

refactor(docker): set up host and cross toolchains via env vars

- Replace standalone host GCC (missing sysroot) with crosstool-ng GCC for host triple, matching cross-compiler quality
- Move all toolchain configuration (CARGO_TARGET_*_LINKER, CC_*, AR_*) into Dockerfiles as ENV, remove cargo config.toml manipulation from build script
- Add LLVM/Clang install step for Darwin images (required by osxcross)
- Handle .exe suffix in binary verification for Windows targets