feat(hooks): Hook Session Lifecycle & Compression Integration

[Edilmo]

Summary

• Adds SessionStart and SessionEnd hook integration with matcher support for different session triggers (startup, resume, clear, compress, exit, logout, prompt_input_exit).
• Adds PreCompress hook integration with matcher support for manual vs automatic compression triggers, allowing hooks to respond appropriately to different compression scenarios.
• Address issues found in #14099 about some hook-system integration tests not work on Windows

Details

This implements session lifecycle hooks with sophisticated matching based on the session trigger source. SessionStart hooks can respond differently to app startup vs chat resume vs clear commands. SessionEnd hooks can handle different termination reasons like graceful exit vs logout vs prompt abandonment. The matching logic allows fine-grained control over when session hooks execute, enabling specialized behavior for different session scenarios. This also implements PreCompress hooks that can respond differently to manual compression (user runs /compress) vs automatic compression (context threshold reached). Hooks can log compression events, ask for user confirmation, or modify compression behavior. The matcher logic distinguishes between manual and auto triggers, enabling different hook behavior for different compression scenarios.

Related Issues

Closes #9138 Closes #9139

How to Validate

• Test SessionStart hooks with different matchers (startup, resume, clear, compress)
• Test SessionEnd hooks with different matchers (exit, clear, logout, prompt_input_exit)
• Verify matcher logic correctly filters hooks based on session trigger
• Test session hook execution adds appropriate context
• Validate session hooks work with different CLI usage patterns
• Test PreCompress hooks with manual trigger (/compress command)
• Test PreCompress hooks with auto trigger (context threshold)
• Verify matcher logic correctly filters based on compression trigger
• Test hook integration with compression workflow
• Validate hooks can influence or log compression events appropriately

Pre-Merge Checklist

• [ ] Updated relevant documentation and README (if needed)
• [x] Added/updated tests (if needed)
• [ ] Noted breaking changes (if any)
• [ ] Validated on required platforms/methods:
  • [x] MacOS
    • [x] npm run
    • [x] npx
    • [ ] Docker
    • [ ] Podman
    • [ ] Seatbelt
  • [ ] Windows
    • [ ] npm run
    • [ ] npx
    • [ ] Docker
  • [ ] Linux
    • [ ] npm run
    • [ ] npx
    • [ ] Docker

[gemini-code-assist[bot]]

Summary of Changes

Hello @Edilmo, I'm Gemini Code Assist[^1]! I'm currently reviewing this pull request and will post my feedback shortly. In the meantime, here's a summary to help you and other reviewers quickly get up to speed!

This pull request significantly enhances the extensibility of the application by integrating new lifecycle hooks for user sessions and content compression. The primary goal is to provide developers with more granular control over these critical events, allowing for custom logic to be executed at specific points, such as application startup, session termination, or before content compression. This improves the system's adaptability to diverse operational scenarios and custom requirements.

Highlights

• Session Lifecycle Hooks: Introduced SessionStart and SessionEnd hooks with comprehensive matcher support. SessionStart hooks can differentiate between app startup, chat resume, or clear commands, while SessionEnd hooks can respond to various termination reasons like graceful exit, logout, or prompt abandonment. This allows for fine-grained control over session-related behaviors.
• Compression Integration Hooks: Added PreCompress hooks that can distinguish between manual compression (e.g., user command) and automatic compression (e.g., context threshold reached). This enables hooks to react differently based on the compression trigger, allowing for custom logging, user confirmation, or modification of compression behavior.
• New Hook Trigger Functions: New utility functions (fireSessionStartHook, fireSessionEndHook, firePreCompressHook) have been added to packages/core/src/core/sessionHookTriggers.ts to facilitate the firing of these new session and compression related hooks through the MessageBus.

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