DOOM DOS browser player: source distribution

Wrapper JavaScript / HTML / CSS: GPL-2.0, available as player-source.zip.
DOOM shareware binaries and game data remain copyrighted by id Software;
they are separate from the emulator and wrapper license.

Pinned emulators npm version: 8.5.2
Verified npm gitHead: 6bbf0925d221a7304ea8e0dda1e89b8dc01569b2
emulators-source.tar.gz: that exact upstream commit, unchanged.
dosbox-source.tar.gz: js-dos/dosbox 528578d5a6f76afd4d5ef4e722b5670826f1183a
sokol-source.tar.gz: floooh/sokol fa3d7cbe9ca85b8b87824ac366c724cb0e33a6af
gl4es-source.tar.gz: ptitSeb/gl4es a744af14d4afbda77bf472bc53f43b9ceba39cc0
GL4ES benchmark traces are omitted; library source code is unchanged.
All archives are available in this same /legal/ directory.

Extract emulators-source.tar.gz. Extract the DOSBox archive into native/dosbox
and sokol into native/sokol-lib, stripping the archive's root directory.
GL4ES is also pinned by CMakeLists.txt to the above commit; the included
archive provides its source independently of GitHub availability.
The upstream Dockerfile documents Emscripten 3.1.28 and the build commands:
yarn install; yarn run gulp wasm; yarn run gulp
Read the upstream README, CMakeLists.txt and gulpfile.ts for build options.
Only wdosbox (not wdosbox-x) is distributed by this player.
The upstream source tree also supports backends not shipped here; those
optional backends may require their own submodules.

Original shareware distribution: doom19s.zip, preserved without changes.
All 20 original extracted files are preserved inside game/doom.jsdos.
The wrapper adds DEFAULT.CFG and .jsdos startup configuration.
SHA-256 values are recorded in sources.json.