[general-purpose] Create test utility file

[sylvansys]

Parent Issue: #311
Agent Type: general-purpose
Branch: 311-fix/can-u-test-out-the-gh-orchestration-plug

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Task Description

Create test utility file

Task Prompt

Create a simple test utility file at plugins/github-orchestration/tests/utils/test-helpers.ts that exports a function formatTestResult(passed: boolean, message: string): string which returns a formatted string like "[PASS] message" or "[FAIL] message".

Keep it simple - just the one function. This is to test the stacked PR workflow hooks.