The Emscripten link embedded data files via magic-relative paths
(../scmos, ../windows/...), which only resolve when the build dir is the
source dir. Split them by which tree the data lives in:
* generated scmos tech files -> ${MAGICDIR}/scmos (the build tree, where
`make techs` writes them);
* verbatim window glyphs -> ${MAGICSRC}/windows/... (the source tree).
Out-of-tree, ../windows/windows7.glyphs pointed at build/windows/ (which
holds only objects) and the link would fail to embed it. In-tree the two
trees coincide, so the resulting .wasm is unchanged.
(Static edit; not runtime-verified — emscripten is not available here.)
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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