v1.0.0 - Initial backend system with JWT, tests, CI, and Docker

Highlights

• Implemented AI image task management APIs
• Added JWT authentication and user-based data isolation
• Added API test case management and execution history
• Added background task processing for the image generation workflow
• Added generated image metadata and local file storage
• Added integration tests with xUnit and WebApplicationFactory
• Added GitHub Actions CI for automated build and test
• Added Docker Compose support for containerized execution

Notes

• Image generation currently uses a mock PNG output.
• Stable Diffusion WebUI / ComfyUI integration is planned as a future enhancement.