memex v0.0.4

Stable release with critical bug fixes and System message type support.

🐛 Bug Fixes

• Critical: Fix sequence increment for incremental writes - messages now correctly ordered
• Fix idle timeout auto-exit in vimo-agent

✨ Features

• Support MessageType::System in compact/output
• HookEvent architecture with context field

Full Changelog: v0.0.4-platform.3...v0.0.4