Add support for new registry/org and registry/user endpoints

[jgamblin]

Summary

This PR implements support for the new CVE Services User Registry endpoints (/registry/org/ and /registry/user/) while maintaining full backward compatibility with the legacy endpoints (/org/ and /user/).

Changes

API Implementation

• Added use_legacy_endpoints parameter to CveApi.__init__() to control endpoint selection
• Implemented helper methods:
  • _org_path() - Builds organization endpoint paths (registry or legacy)
  • _user_path() - Builds user endpoint paths (registry or legacy)
• Updated all org/user methods to use new registry endpoints by default:
  • quota()
  • show_user()
  • reset_api_key()
  • create_user()
  • update_user()
  • list_users()
  • show_org()

CLI Support

• Added --legacy flag to CLI for easy switching to legacy endpoints
• Updated Config class to handle the legacy flag and pass it to CveApi

Backward Compatibility

• All existing code continues to work without changes (registry endpoints used by default)
• Users can opt-in to legacy endpoints using the --legacy flag
• Both endpoint modes fully tested and validated

Testing

• Added TestRegistryEndpoints class with 12 comprehensive tests
• Tests verify correct endpoint selection for both registry and legacy modes
• All endpoints tested:
  • Organization quota
  • User CRUD operations
  • User API key reset
  • Organization info
• All 49 tests pass (37 existing + 12 new)

Usage

Using new registry endpoints (default):

cve -u username -o org -a api_key org
cve -u username -o org -a api_key user show jane@example.com

Using legacy endpoints:

cve -u username -o org -a api_key --legacy org
cve -u username -o org -a api_key --legacy user show jane@example.com

Programmatic usage:

# Using new registry endpoints
cve_api = CveApi(username="user", org="org", api_key="key")

# Using legacy endpoints
cve_api = CveApi(username="user", org="org", api_key="key", use_legacy_endpoints=True)

Resolves

Closes #112 - Add new registry/user and registry/org CVE Services endpoints