feat(hooks): Hook Telemetry Infrastructure

[Edilmo]

TLDR

Adds complete telemetry support for hook execution with structured logging and metrics collection for observability and debugging.
Part of full hook system implementation here

Dive Deeper

This implements the observability requirement for Hooks. The HookCallEvent class captures all relevant hook execution data (event name, hook type, input/output, duration, success/failure). The logHookCall function provides structured logging, while recordHookCallMetrics tracks performance metrics. This telemetry is essential for debugging hook issues and monitoring system performance.

Reviewer Test Plan

• Run telemetry tests to verify event structure
• Test hook execution generates proper telemetry events
• Verify metrics collection works for both successful and failed hook executions
• Check telemetry includes all required fields (duration, success, error details)

Testing Matrix

	🍏	🪟	🐧
npm run	✅	❓	❓
npx	✅	❓	❓
Docker	❓	❓	❓
Podman	❓	-	-
Seatbelt	❓	-	-

Linked issues / bugs

Closes #9081

[gemini-code-assist]

Summary of Changes

Hello @Edilmo, I'm Gemini Code Assist¹! 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 establishes a robust telemetry infrastructure for the newly introduced hook system. It aims to provide deep insights into hook executions by capturing detailed event data, logging structured information, and collecting performance metrics. This foundational work is essential for monitoring the health, performance, and behavior of hooks, enabling efficient debugging and system optimization within the CLI.

Highlights

• Hook Telemetry Infrastructure: Introduced comprehensive telemetry support for hook execution, including structured logging and metrics collection for enhanced observability and debugging.
• New Hook Types and Configuration: Defined new enums (HookEventName, HookType) and interfaces (HookConfig, HookDefinition) for configuring hooks, and integrated these into the CLI's configuration and settings schema.
• LLM Request/Response Translation: Added a HookTranslator class, specifically HookTranslatorGenAIv1, to facilitate seamless conversion between GenAI SDK types and stable Hook API types for LLM requests, responses, and tool configurations.
• Detailed Hook Call Events: Implemented a HookCallEvent class to capture all relevant hook execution data, such as event name, hook type, input/output, duration, success/failure, and error details.
• Metrics and Logging Integration: Integrated logHookCall for structured logging of hook events and recordHookCallMetrics for tracking performance metrics like call count and latency, enhancing the existing telemetry system.

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[gemini-code-assist]

Code Review

This pull request introduces a comprehensive telemetry and observability infrastructure for the new hook system, which is a great addition for debugging and monitoring. The changes include new configuration schemas, telemetry events, metrics, and a well-designed set of types for hooks. The introduction of a hookTranslator to decouple the hook API from the GenAI SDK is a solid architectural choice. However, I've found a critical issue in the implementation of the hookTranslator concerning the handling of GenerateContentResponse, which could lead to runtime errors. This needs to be addressed to ensure the stability of the new hook system.