Setup installs deps, builds @ymir/types and @ymir/wasm, and compiles the Node WASM engine (best-effort if Emscripten is present). Run scripts: dev (api+web via concurrently, wired to CONDUCTOR_PORT), api, web, test, wasm. Concurrent-safe (per-worktree SQLite, per-workspace ports). Adds concurrently devDependency. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>