Build: ship the launcher instead of bundling the JS engine

readSourceFiles no longer copies cli/engine into the skill; the scripts
payload is the launcher (executable bit preserved through dist, plugin/, and
universal.zip), impeccable.cmd, VERSION (synced from ENGINE_VERSION on every
build), the page JS, and command-metadata.json. Hook manifests call
`<scripts>/impeccable hook` behind an existence guard (Codex adds a
commandWindows sibling calling impeccable.cmd; Cursor runs hook-before-edit;
GitHub keeps the git rev-parse form; Grok mirrors Claude); the Node probe and
systemMessage notice are gone. build:release fetches the pinned engine for
every target (lenient) and stages bin/<os-arch>/ into the dist skill copies
after root harness dirs and plugin/ were synced, so git-delivered trees stay
launcher-only. The detection-rule count check reads the vendored
extension/detector/antipatterns.json and is skipped when absent.
build:browser is a stub; the codex prefix rewrite leaves
`{{scripts_path}}/impeccable` alone.

Prepared with AI assistance (Claude Code).

package.json

@@ -65,8 +65,6 @@
     "test:skill-behavior": "node scripts/run-tests.mjs skill-behavior",
     "test:live-svelte-adapter-deepseek": "node scripts/run-tests.mjs live-svelte-adapter-deepseek",
     "smoke:hooks": "node scripts/smoke-provider-hooks.mjs",
-    "bench:detector": "node scripts/benchmark-detector.mjs",
-    "bench:detector:browser": "node scripts/benchmark-detector.mjs --browser",
     "audit": "bun audit --audit-level=moderate",
     "prepack": "cp README.md README.repo.md && cp README.npm.md README.md",
     "postpack": "cp README.repo.md README.md && rm README.repo.md",