docs: Document test infrastructure, security fix, common pitfalls reorganization, and CI/CD pipeline
MANDATORY DOCUMENTATION UPDATE (4 PRs):
1. Test Infrastructure (PR #2): 113 tests, coverage requirements, how to run
2. Security Fix (PR #3): Expanded Pitfall #72 with process details
3. Common Pitfalls (PR #1): Reorganization structure and benefits
4. CI/CD Pipeline (PR #5): 4 workflows, troubleshooting, branch protection
Restores compliance with mandatory git commit + documentation workflow
(lines 217-256 of copilot-instructions.md).
Related PRs: #1, #2, #3, #5
Co-authored-by: mindesbunister <32161838+mindesbunister@users.noreply.github.com>
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