Fork of @atproto/lex-builder for web-based lexicon resolution.

The official package doesn't export LexDefBuilder (the class that does actual codegen), only the high-level build() function that writes to disk. We need in-memory codegen for serving TypeScript dynamically from a web endpoint.

All modifications are marked with [PATCH: inlay.at] comments.

• Added export * from './lex-def-builder.ts' to expose LexDefBuilder

• Added flatImports and importSuffix options to RefResolverOptions
• Modified resolveExternal() to generate flat relative imports (./nsid.ts) when flatImports is true (original generates path-based imports like ../foo/bar.defs.ts)

• Changed imports from npm: specifiers with pinned versions for Deno/Val Town compatibility
• Changed local imports from .js to .ts extensions

Source: https://github.com/bluesky-social/atproto/tree/main/packages/lex-builder Version: 0.0.3 (circa Feb 2025)