fix: generate sourcemap with hires (#687) (#688)

Co-authored-by: Anthony Fu <anthonyfu117@hotmail.com>

src/core/transformer.ts

@@ -32,7 +32,7 @@ export default function transformer(ctx: Context, transformer: SupportedTransfor
 
     const result: TransformResult = { code: s.toString() }
     if (ctx.sourcemap)
-      result.map = s.generateMap({ source: id, includeContent: true })
+      result.map = s.generateMap({ source: id, includeContent: true, hires: 'boundary' })
     return result
   }
 }