[Docs] Update API and User Documentation #1520

Description

As a DataFed user and developer, I want comprehensive documentation for the new metadata-only repository feature so that I can understand how to use and integrate with this new functionality.

Acceptance Criteria

• Update API documentation to include:
  • New type field in repository creation endpoints
  • Response format changes for allocation operations
  • Examples for both GLOBUS and METADATA_ONLY repository types
• Update user guides to explain:
  • When to use metadata-only repositories vs Globus repositories
  • How to create each type of repository
  • Limitations and capabilities of metadata-only repositories
• Add migration guide for developers:
  • How to prepare code for Rust migration
  • Design patterns to use/avoid
  • Testing strategies during migration
• Update configuration documentation:
  • New environment variables
  • Feature flag usage
  • Service registry configuration
• Create troubleshooting guide:
  • Common issues and solutions
  • How to verify repository type
  • Debugging allocation failures

Resources

• API Specifications: spec.md#L610-L863
• Configuration Management: spec.md#L865-L1222
• Repository Type System: spec.md#L97-L168

Dependencies

• Depends on: [Foxx, Core] Repository Type System: Implement Type Enum and Validation #1514, [Foxx] Foxx API Updates: Update Repository and Allocation Endpoints for Type Support #1515, [Core, Arango] Database Migration: Add Repository Type Field to Database Schema #1516, [Core] C++ Response Handling: Update Core Service for New Allocation Response Format #1517
• Should be completed alongside implementation tasks

Notes

• Documentation should be written for both technical and non-technical audiences
• Include clear examples and use cases
• Consider adding diagrams to illustrate repository type differences