1. Add [rewatch](https://github.com/teamwalnut/rewatch) to compiler repo + CI + the rescript npm package (as an experimental alternative to bsb) 2. Use rewatch to build the standard libraries (OCaml stdlib, Caml_*, Belt, Js) 3. (Move Core into the compiler, move other stdlibs out of the compiler, ...) 4. Remove bsb, do not ship any compiled stdlib artifacts with the ReScript npm package anymore (see https://github.com/rescript-lang/rescript-compiler/issues/6183)