Summary

Addresses #1367 - Adds comprehensive documentation for building Katana without CGO dependency.

Changes

BUILDING.md

• Added standard build instructions (with CGO)
• Added pure Go build instructions (without CGO)
• Added cross-compilation examples for macOS, Windows, Linux
• Documented build tags and their effects

README.md

• Updated installation section with pure Go option
• Added notes about jsluice dependency and CGO requirements
• Clarified feature limitations of pure Go builds

Build Tags

• without_jsluice - Disables jsluice JavaScript endpoint extraction (removes CGO dependency)

Impact

✅ No breaking changes - Documentation only ✅ All features preserved - Pure Go builds work with all features except jsluice ✅ Better cross-platform support - Easier cross-compilation

Related Issue

Fixes: #1367

/claim #1367