Summary

Part of Phase 3 (C++20 Module Stabilization) from #275.

Update documentation to reflect stable C++20 module support.

Parent Issue

• [MODULE] Phase 3: C++20 Module Stabilization #275 (C++20 Module Stabilization)
• EPIC: [EPIC] C++20 Module Migration - Cross-System Preparation #256

Tasks

• Update README.md - remove "experimental" from module references
• Update README_KO.md with same changes
• Add module usage examples to documentation
• Create MODULE_MIGRATION.md guide
• Update ARCHITECTURE.md with module structure
• Document compiler compatibility and limitations

Files to Update

• README.md
• README_KO.md
• docs/ARCHITECTURE.md
• docs/guides/ (new guide if needed)

Acceptance Criteria

• No "experimental" references for C++20 modules
• Clear documentation for module usage
• Compiler compatibility clearly documented