It would be nice to have these warnings / errors.

• NAMESPACE_CONFLICT (rollup, enabled by default, REPL), ambiguous-reexport (esbuild, not enabled by default, try): Rolldown REPL
• CIRCULAR_REEXPORT (rollup, error, REPL), Detected cycle while resolving import (esbuild, error, try): Rolldown REPL (broken output) -> feat: add CIRCULAR_REEXPORT error #7337
• MISSING_NAME_OPTION_FOR_IIFE_EXPORT (rollup, warning, REPL): Rolldown REPL (it is an error with UMD output and that is implemented)
• SOURCEMAP_BROKEN (rollup, warning, implementation)