feat(webworker): browser worker host runtime and the vfs image packer

Two private experimental packages run the whole harness tree inside one
dedicated Web Worker. dsh-experimental-webworker-runtime owns the in-memory
VFS (BigInt stats with per-path identity and strictly increasing mtimes),
the CommonJS wrapper loader over a lazily-evaluated builtin table whose
shims typecheck against Node's own module types, the postMessage tunnel
speaking plain HTTP, the AsyncLocalStorage runtime, and the worker
assembly. dsh-experimental-webworker-packer lowers every module body at
pack time against the shared wrapper contract, sweeps the profile closure
by static reachability, and writes a deterministically gzip-compressed tar
the worker inflates through the browser's native DecompressionStream while
it downloads.

THIRD_PARTY_NOTICES.md

@@ -39,6 +39,7 @@ External packages that a workspace package resolves at runtime. The tier covers
 | [`@joplin/turndown-plugin-gfm`](https://github.com/laurent22/joplin-turndown-plugin-gfm) | MIT |
 | [`@jridgewell/gen-mapping`](https://github.com/jridgewell/sourcemaps) | MIT |
 | [`@modelcontextprotocol/sdk`](https://github.com/modelcontextprotocol/typescript-sdk) | MIT |
+| [`@noble/hashes`](https://github.com/paulmillr/noble-hashes) | MIT |
 | [`@openai/codex`](https://github.com/openai/codex) | Apache-2.0 |
 | [`@opentelemetry/api`](https://github.com/open-telemetry/opentelemetry-js) | Apache-2.0 |
 | [`@opentelemetry/api-logs`](https://github.com/open-telemetry/opentelemetry-js) | Apache-2.0 |
@@ -51,7 +52,10 @@ External packages that a workspace package resolves at runtime. The tier covers
 | [`@tanstack/react-virtual`](https://github.com/TanStack/virtual) | MIT |
 | [`@types/mdast`](https://github.com/DefinitelyTyped/DefinitelyTyped) | MIT |
 | [`@vscode/ripgrep`](https://github.com/microsoft/vscode-ripgrep) | MIT |
+| [`@yarnpkg/parsers`](https://github.com/yarnpkg/berry) | BSD-2-Clause |
+| [`acorn`](https://github.com/acornjs/acorn) | MIT |
 | [`anser`](https://github.com/IonicaBizau/anser) | MIT |
+| [`buffer`](https://github.com/feross/buffer) | MIT |
 | [`chokidar`](https://github.com/paulmillr/chokidar) | MIT |
 | [`clsx`](https://github.com/lukeed/clsx) | MIT |
 | [`commander`](https://github.com/tj/commander.js) | MIT |
@@ -136,6 +140,7 @@ External packages **directly declared** only by repository tooling, test infrast
 | [`@types/react-dom`](https://github.com/DefinitelyTyped/DefinitelyTyped) | MIT |
 | [`@types/spdx-expression-parse`](https://github.com/DefinitelyTyped/DefinitelyTyped) | MIT |
 | [`@types/turndown`](https://github.com/DefinitelyTyped/DefinitelyTyped) | MIT |
+| [`@types/use-sync-external-store`](https://github.com/DefinitelyTyped/DefinitelyTyped) | MIT |
 | [`@types/ws`](https://github.com/DefinitelyTyped/DefinitelyTyped) | MIT |
 | [`@vitejs/plugin-react`](https://github.com/vitejs/vite-plugin-react) | MIT |
 | [`@vitest/coverage-v8`](https://github.com/vitest-dev/vitest) | MIT |
@@ -148,6 +153,7 @@ External packages **directly declared** only by repository tooling, test infrast
 | [`eslint-plugin-sonarjs`](https://github.com/SonarSource/SonarJS) | LGPL-3.0-only |
 | [`execa`](https://github.com/sindresorhus/execa) | MIT |
 | [`fast-check`](https://github.com/dubzzz/fast-check) | MIT |
+| [`http-server`](https://github.com/http-party/http-server) | MIT |
 | [`istanbul-lib-report`](https://github.com/istanbuljs/istanbuljs) | BSD-3-Clause |
 | [`jscpd`](https://github.com/kucherenko/jscpd) | MIT |
 | [`jsdom`](https://github.com/jsdom/jsdom) | MIT |