Run integration tests in CI

[cte]

Description

Clean up our integration tests and run them in CI.

Type of change

• Bug fix (non-breaking change which fixes an issue)
• New feature
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

How Has This Been Tested?

Checklist:

• My code follows the patterns of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation

Additional context

Related Issues

Reviewers

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Important

Add integration tests to CI workflow with necessary configurations and updates.

• CI Workflow:
  • Adds integration-test job to code-qa.yml for macOS, with conditional Linux support using xvfb-run.
  • Adds workflow_dispatch to trigger workflows manually.
• Configuration:
  • Introduces .env.integration.example for environment variables.
  • Adds tsconfig.integration.json for integration test compilation.
  • Updates package.json scripts to include compile:integration and test:extension.
• Code Changes:
  • Modifies ClineProvider in ClineProvider.ts to expose messages for testing.
  • Refactors extension.test.ts and adds task.test.ts for integration tests.
• Environment:
  • Adds flake.nix and flake.lock for Nix-based development environment setup.

^{This description was created by for eda5680. It will automatically update as commits are pushed.}

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Latest commit: eda5680

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