Third-party code in qjs_guest.wasm

qjs_guest.wasm is compiled from the following, all under permissive licences
that allow redistribution in binary form with this notice:

- QuickJS-ng 0.7.0 (quickjs/): MIT. Copyright (c) 2017-2021 Fabrice Bellard,
  Copyright (c) 2017-2021 Charlie Gordon, Copyright (c) 2023 Ben Noordhuis,
  Copyright (c) 2023 Saul Ibarra Corretge. The full text is in quickjs/LICENSE.
  This directory contains the unmodified upstream sources except for the two
  changes listed in PATCHES.md.
- wasi-libc, linked in by the toolchain: Apache-2.0 WITH LLVM-exception, MIT
  and BSD-2-Clause parts (the libm, string and stdio code derives from musl,
  MIT).
- LLVM compiler-rt builtins, linked in by the toolchain: Apache-2.0 WITH
  LLVM-exception.

Build tooling (not shipped): zig 0.16.0 (MIT), which bundles clang 21.1.0
(Apache-2.0 WITH LLVM-exception) and wasi-libc. glue.c is original PDFluent
code under the repository licence.
