feat: add Claude and Copilot setup documentation

[btotharye]

• Add .claude/instructions.md with architecture, patterns, and development workflow
• Add .github/copilot-training.md with code examples and testing patterns
• Add DEVELOPMENT.md with branching strategy, PR requirements, and common tasks
• Provides AI-friendly documentation for code generation and review
• Includes testing standards, linting requirements, and troubleshooting

Description

Type of Change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Content pack addition/update
• CI/CD or tooling change

Changes Made

Testing

• Tests pass locally (make test)
• Linting passes (make lint)
• Formatting is correct (make format-check)
• Tested manually with:

Related Issues

Checklist

• My code follows the project's style guidelines
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings or errors
• I have added tests that prove my fix is effective or that my feature works
• New and existing tests pass locally with my changes

Additional Notes

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.41%. Comparing base (e7da490) to head (ab30ede).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main      #59   +/-   ##
=======================================
  Coverage   94.41%   94.41%           
=======================================
  Files          33       33           
  Lines        3655     3655           
=======================================
  Hits         3451     3451           
  Misses        204      204           

Flag	Coverage Δ
unittests	94.41% <ø> (ø)

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