chore(example): context propagation and signal-based cancellation

[appleboy]

• Add signal handling to gracefully cancel the context on interrupt (SIGINT)
• Update functions to accept context instead of creating a new one internally
• Pass the main context to MCP transport constructors for improved cancellation support

[gemini-code-assist]

Summary of Changes

Hello @appleboy, 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 refactors the mcp example to enhance its robustness and responsiveness to system signals. It introduces a centralized context that can be cancelled via SIGINT or SIGTERM, and propagates this context throughout the MCP transport initialization and connection processes. This ensures that long-running operations and network clients can be gracefully shut down when the application receives an interrupt signal, improving overall application stability.

Highlights

• Signal-based Context Cancellation: The application now gracefully handles interrupt signals (SIGINT, SIGTERM) by integrating signal.NotifyContext into the main context, ensuring proper shutdown of ongoing operations.
• Improved Context Propagation: Functions responsible for creating MCP transports (localMCPTransport, githubMCPTransport) have been refactored to accept and utilize a context.Context parameter, replacing internal context.Background() calls for better cancellation support.
• Enhanced MCP Transport Initialization: The main application context is now explicitly passed to MCP transport constructors, allowing for consistent cancellation behavior across the application's lifecycle, including network clients and in-memory servers.

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[gemini-code-assist]

Code Review

This pull request is a great improvement, refactoring the MCP example to properly propagate context and handle termination signals for graceful cancellation. The changes are clean and follow Go best practices. I have one suggestion to improve the portability of the signal handling code.

[dpasiukevich]

Hi,

All examples use in-memory services, so the data will be lost anyway. Let's only add it to MCP example (where it's needed for github mcp flow)?

Thanks!

[appleboy]

@dpasiukevich revert the last commit. Thanks for your feedback.

[dpasiukevich]

Thanks!

[appleboy]

@dpasiukevich can you merge the PR?

[dpasiukevich]

@appleboy it should be possible to merge yourself, you only needed to mark comments as resolved. Let me know if that was not the case.