Create contributing guide and issue templates

[clencyc]

Description

Add CONTRIBUTING.md and GitHub issue templates to make it easier for new contributors to get started.

Acceptance Criteria

• CONTRIBUTING.md created with:
  • How to set up dev environment
  • How to run tests
  • Code style guidelines
  • Git commit message conventions
  • Pull request process
  • How to report bugs
• Bug report issue template
• Feature request issue template
• Pull request template
• .github/ISSUE_TEMPLATE/bug_report.md
• .github/ISSUE_TEMPLATE/feature_request.md
• .github/pull_request_template.md
• Link to contributing guide in README

Files to Create

• CONTRIBUTING.md - main contributing guidelines
• .github/ISSUE_TEMPLATE/bug_report.md
• .github/ISSUE_TEMPLATE/feature_request.md
• .github/pull_request_template.md

Template Content Should Include

• Clear steps to follow
• Example formatting
• What information to include
• Labels to apply

Difficulty: Easy

Estimated time: 2-3 hours