JIT Regression Test Extraction

🚨 Do NOT create a test when: the issue has no reproducible code and you cannot compose a minimal repro, the issue is a duplicate of an existing test under JitBlue/, or the bug is in libraries/runtime rather than the JIT compiler itself.

Extract a JIT regression test case from a GitHub issue into a properly structured test under src/tests/JIT/Regression/JitBlue/.

Step 1: Gather Information from the GitHub Issue

From the GitHub issue, extract:

1. Issue number → folder/file name (e.g., #99391 → Runtime_99391)
2. Reproduction code — if none provided, compose a minimal repro yourself
3. Environment variables — any DOTNET_* vars needed to reproduce
4. Expected behavior — correct output/behavior

Step 2: Create the Test Directory

Create a new folder under src/tests/JIT/Regression/JitBlue/: