refactor(mcp): use getDefaultEnvironment for stdio client transport

[samhvw8]

• Replace manual PATH and HOME env var handling with getDefaultEnvironment()
• Improves consistency and reliability of MCP client environment setup
• Leverages SDK's built-in environment configuration

Related GitHub Issue

Closes: #4257

Description

Test Procedure

Type of Change

• 🐛 Bug Fix: Non-breaking change that fixes an issue.
• ✨ New Feature: Non-breaking change that adds functionality.
• 💥 Breaking Change: Fix or feature that would cause existing functionality to not work as expected.
• ♻️ Refactor: Code change that neither fixes a bug nor adds a feature.
• 💅 Style: Changes that do not affect the meaning of the code (white-space, formatting, etc.).
• 📚 Documentation: Updates to documentation files.
• ⚙️ Build/CI: Changes to the build process or CI configuration.
• 🧹 Chore: Other changes that don't modify src or test files.

Pre-Submission Checklist

• Issue Linked: This PR is linked to an approved GitHub Issue (see "Related GitHub Issue" above).
• Scope: My changes are focused on the linked issue (one major feature/fix per PR).
• Self-Review: I have performed a thorough self-review of my code.
• Code Quality:
  • My code adheres to the project's style guidelines.
  • There are no new linting errors or warnings (npm run lint).
  • All debug code (e.g., console.log) has been removed.
• Testing:
  • New and/or updated tests have been added to cover my changes.
  • All tests pass locally (npm test).
  • The application builds successfully with my changes.
• Branch Hygiene: My branch is up-to-date (rebased) with the main branch.
• Documentation Impact: I have considered if my changes require documentation updates (see "Documentation Updates" section below).
• Changeset: A changeset has been created using npm run changeset if this PR includes user-facing changes or dependency updates.
• Contribution Guidelines: I have read and agree to the Contributor Guidelines.

Screenshots / Videos

Documentation Updates

Additional Notes

Get in Touch

---

Important

Refactor McpHub.ts to use getDefaultEnvironment() for MCP client environment setup, replacing manual PATH and HOME handling.

• Environment Setup:
  • Replaces manual PATH and HOME environment variable handling with getDefaultEnvironment() in McpHub.ts.
  • Enhances consistency and reliability of MCP client environment setup.
• Imports:
  • Adds getDefaultEnvironment to imports from @modelcontextprotocol/sdk/client/stdio.js.

^{This description was created by for e91bfbcd1a96c81c591ffb6b65db6430e9d7da64. You can customize this summary. It will automatically update as commits are pushed.}

[daniel-lxs]

To make sure everything works well, we should consider adding a test case in src/services/mcp/__tests__/McpHub.test.ts that specifically verifies the connectToServer method correctly passes the environment from getDefaultEnvironment() (along with any custom configInjected.env) to the StdioClientTransport constructor for stdio-type servers. This could involve spying on the StdioClientTransport constructor or examining the arguments it receives.

This would provide explicit confirmation that McpHub correctly utilizes the SDK's environment function as intended.

[daniel-lxs]

This looks good, for reference here's the function being used from the SDK, it correctly injects HOME and PATH and correctly handles the OS specific ones:

https://github.com/modelcontextprotocol/typescript-sdk/blob/590d4841373fc4eb86ecc9079834353a98cb84a3/src/client/stdio.ts#L66

[samhvw8]

This looks good, for reference here's the function being used from the SDK, it correctly injects HOME and PATH and correctly handles the OS specific ones:

https://github.com/modelcontextprotocol/typescript-sdk/blob/590d4841373fc4eb86ecc9079834353a98cb84a3/src/client/stdio.ts#L66

thanks for clarify for me :D