- Add NudgeChannels field to MessagingConfig struct in types.go - Initialize NudgeChannels map in NewMessagingConfig() - Add validation in validateMessagingConfig(): channel names must be non-empty and each channel must have at least one recipient - Add tests for valid nudge channels and empty recipient validation 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>