Add comprehensive repository analysis and technical review

[Copilot]

Comprehensive technical review of pySDC codebase covering architecture, code quality, testing, documentation, dependencies, and security posture.

Deliverable

REPOSITORY_ANALYSIS.md - 10-section technical assessment with metrics, findings, and prioritized recommendations.

Key Findings

Strengths (4.5/5 overall)

• Clean hierarchical OOP with plugin architecture (50+ problem classes, 20+ sweepers)
• Comprehensive multi-environment testing (5 environments × 4 Python versions)
• Professional documentation (9-step tutorial, academic citations, contributing guide)
• Active maintenance with clear funding and community

Critical Gaps

• No type hints in core modules (Python 3.10+ available)
• Loose dependency constraints (numpy>=1.15.4 spans breaking changes)
• Missing security policy (SECURITY.md)
• os.system() calls instead of subprocess

Recommendations Priority

High: Type hints, SECURITY.md, dependency pinning, subprocess migration
Medium: Pre-commit hooks, API docs expansion, integration test docs
Low: Mutation testing, cookbook recipes, SBOM generation

Metrics

• 866 Python files, 13 core modules, 6 implementation categories
• 100+ tests, 70-100% coverage, timeout 300s
• 17+ independent research projects
• 8 core dependencies, 4 optional groups

---

💡 You can make Copilot smarter by setting up custom instructions, customizing its development environment and configuring Model Context Protocol (MCP) servers. Learn more Copilot coding agent tips in the docs.