renderer-bundle.ts shipped in #85887 as pure/injectable but had no unit
coverage. Lock the contract that heals a torn self-update: the boot loader
must prefer a complete generation and only report a repair when every copy
is torn.
parseModuleAssetRefs: module scripts + modulepreload only (not stylesheets
or classic scripts), CDN/absolute refs dropped, ./ and query/hash stripped.
missingRendererAssets: intact -> [], torn -> the dangling chunk(s),
per-copy dir-relative existence (the split app.asar vs app.asar.unpacked
case), and an unreadable/module-free index is not treated as torn.