Task 1.1: Design and Implement Core Authentication Interfaces

[slin1237]

Description: Define the core interfaces that all authentication providers must implement. This includes the main Credentials interface and supporting types for token management, HTTP client configuration, and service endpoint resolution.

Dependencies: None

Deliverables:

• pkg/auth/interfaces.go with Credentials, TokenProvider, CredentialsProvider interfaces
• Provider and AuthType enums integrated in interfaces.go
• Config struct with fallback support in interfaces.go
• pkg/auth/errors.go with authentication-specific error types (not yet implemented)

Implementation Status:

• Credentials interface with Provider(), Type(), Token(), SignRequest(), Refresh(), IsExpired()
• TokenProvider interface with GetToken() and RefreshToken()
• CredentialsProvider interface for credential resolution
• ChainProvider for fallback authentication
• HTTPTransport for automatic request signing
• All provider types (OCI, AWS, GCP, Azure, GitHub) defined
• All auth types for each provider defined

Acceptance Criteria:

• Credentials interface supports authentication operations
• TokenProvider interface supports token management
• Error types need to be implemented
• All interfaces have godoc documentation
• Unit tests validate interface contracts