Klain Modules Package

klmpm Stage 1: compiler-side package resolution — a bare specifier (`import x from 'pkg'`, no `./`/`../`) resolves against klain_modules/<name>/klain.json's "main" field, found by walking upward from this file's own directory. klmpm itself (the tool that would fetch a real dependency into klain_modules/) doesn't exist yet — the klain_modules/greeter directory alongside this file was hand-written to exercise the exact same resolution path a real fetched package would.