Add commit message template and guidelines

[zeroecco]

Summary

This PR adds commit message standardization resources to help contributors follow the ZIR-XXX format enforced by the commit-msg hook.

Changes

• .gitmessage: Git commit message template with ZIR-XXX format and inline help
• COMMIT_GUIDELINES.md: Comprehensive documentation covering:
  • Required format specification
  • Good and bad examples
  • Setup instructions
  • Common errors and troubleshooting
  • Best practices
• CONTRIBUTING.md: General contribution guidelines with commit format requirements

Benefits

• Reduces commit rejections from the commit-msg hook
• Provides upfront guidance instead of error-based learning
• Improves commit message consistency across the project
• Makes it easier for new contributors to follow project conventions

Usage

Contributors can configure the template with:

git config commit.template .gitmessage

Then git commit (without -m) will open their editor with the template pre-filled.

Test plan

• Created .gitmessage template file with proper format
• Created comprehensive COMMIT_GUIDELINES.md
• Created CONTRIBUTING.md with commit format requirements
• Verified commit message follows ZIR-XXX format
• Tested git config for template setup

🤖 Generated with Claude Code