docs: add Korean problem-first guide

Expose multilingual machine-discovery indexes

Add Korean reader and machine-discovery links

Clarify external mirror provenance

Add licensed full-text mirror and machine-readable article

Link focused evidence notes

Improve scholarly discovery metadata and preserve full-text links

Link searchable full-text paper formats

Link maintained multilingual paper and research guides

Link the public result-summary collection

Publish validated paper result summary

initial commit