Constant EXTENSION_SCAN_DENY_LIST 

const EXTENSION_SCAN_DENY_LIST: &[&str];

Directory names that are never extensions themselves even though they sit at the top level of extensions/. VS Code’s shipped tree keeps TypeScript type declarations in types/, build output in out/, and a flat node_modules/ for shared dependencies. Scanning into those emits noise like [ExtensionScanner] Could not read package.json at .../out/package.json on every boot; callers use ExtensionScanDenyList to skip them without losing the ability to scan nested node_modules inside a real extension (e.g. a language server’s bundled deps).