Archived obsolete Ping-Service documentation (`ping-service.md`, `PingService.md`) and replaced them with updated references (`PingService_Reference.md`, `Testing_with_Postman.md`). Improved clarity and organization of backend guides with a focus on current architecture, testing approaches, and microservice design principles. Documented the transition with a session log for traceability.
Implemented a standardized folder structure for domain documentation to improve clarity and maintainability. Migrated existing files to the new structure, updated links in related documentation, and added README files for navigation and guidance.
