Add standard Ed-Fi boilerplate files

[stephenfuqua]

Summary

Added standard Ed-Fi boilerplate files to establish consistent repository documentation and legal compliance across the organization:

• LICENSE - Apache License 2.0
• CODE_OF_CONDUCT.md - Ed-Fi community code of conduct
• CONTRIBUTORS.md - Contributor list template
• NOTICES.md - Third-party software notices and copyright
• README.md - Enhanced with legal information footer

Test plan

• All files created successfully in repository root
• LICENSE file present and properly formatted
• CODE_OF_CONDUCT references governance contact
• CONTRIBUTORS references correct GitHub repository path
• NOTICES updated with repository name
• README enhanced with legal information section (existing documentation preserved)

🤖 Generated with Claude Code

[stephenfuqua]

I didn't expect this PR to land in Crocus's repository. Closing and re-opening directly in the Ed-Fi-Exchange-OSS organization.