- Correctly construct cmake cmdline for wasmstdlib including cmake common host options. This is required in order to include e.g. `CMAKE_OSX_SYSROOT` on macOS, etc.
- Ensure we're passing path to newly-built SDK to sil-opt
This makes almost every AutoDiff tests passing for Wasm target (the only exception is `AutoDiff/validation-test/always_emit_into_client/multi_module_struct_no_jvp.swift` as `expectCrash()` is not working properly on Wasm.