Run bare rust CLI binary, no node

[alexeagle]

It's slow to start a NodeJS process for every spawn of swc, and it's extra weight to send to remote execution service.

SWC has a binary codenamed "swcx" which is the bare Rust binary without the node binding. This should be suitable for use in Bazel.

https://github.com/aspect-build/rules_swc/pull/57 has some longstanding WIP for this, but it needs a sponsor to fund the rest of the work.