X_TYPESCRIPT_VERSION
Means
The app declares a TypeScript older than the one x new scaffolds
Typical cause
a package.json's typescript range admits a compiler below the scaffold's TYPESCRIPT_VERSION (packages/cli/src/templates/scaffold-repo.ts); the framework's own source and .d.ts are checked by that compiler, so typecheck and build go red on files the app never wrote — x doctor and x upgrade name each lagging manifest
Fix
x doctor --json — each X_TYPESCRIPT_VERSION finding names its manifest and the bun add that moves it