Fold documentation-plan and progress into development.md, drop docs/archive,
retarget live links, and point README plus agent-rules at the new home.
Co-Authored-By: Composer <noreply@cursor.com>
Co-authored-by: Cursor <cursoragent@cursor.com>
development.md and agent-rules.mdc in English; progress.md and roadmap.md stay Russian as internal docs.
Co-authored-by: Cursor <cursoragent@cursor.com>