[ef-38] feat: add SessionEnd hook + fix Notification policy in example

[NiveditJain]

Summary

• Add slack-on-session-end policy for SessionEnd events in the notification example
• Await fetch with AbortSignal.timeout(5000) so Slack requests complete before process.exit() is called
• Return instruct() instead of allow() so Claude knows the notification was sent
• Remove the idle-only filter — the handler now fires on all notification types

Test plan

• Set SLACK_WEBHOOK_URL and run failproofai p -i -c examples/policies-notification.js; let Claude go idle — confirm Slack message arrives
• Exit a Claude session with the hook active — confirm session-end Slack message arrives
• Unset SLACK_WEBHOOK_URL — confirm both policies return allow() silently

🤖 Generated with Claude Code

Summary by CodeRabbit

• New Features
  • Slack notifications now posted for idle events and session end events
  • Enhanced notification reliability with timeout protection and improved error handling

[coderabbitai]

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Free

Run ID: 58761858-4319-4bee-beb4-94ad24a5fa74

📥 Commits

Reviewing files that changed from the base of the PR and between 799025a and 830539a.

📒 Files selected for processing (1)

• examples/policies-notification.js

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📝 Walkthrough

Walkthrough

Updated an example policy file to enhance Slack notifications by replacing fire-and-forget fetch calls with awaited requests that include 5-second timeouts and error handling. Added a new policy rule to notify Slack on SessionEnd events, and modified the idle notification handler to always post messages and return instruct() instead of allow().

Changes

Cohort / File(s)	Summary
Notification Handler Enhancement examples/policies-notification.js	Modified idle notification handler to remove type filtering, post to Slack with timeout/retry logic, and return instruct(). Added new slack-on-session-end policy rule for SessionEnd events with similar awaited Slack posting and error-swallowing pattern.

Estimated code review effort

🎯 3 (Moderate) | ⏱️ ~20 minutes

Poem

🐰 Hop-hop, the notifications now flow,
With Slack messages reaping what our sessions sow,
No more fire-and-forget, we await with grace,
SessionEnd and Idle both find their place,
A timeout of five brings peace to our race! 🔔

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Note

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