Add comprehensive XML documentation (param/returns tags) across 132 source files to improve IntelliSense and API discoverability. Include ConfigManager design documents and implementation plans for phases 1-9.
Move DTOs from ApiContracts to appropriate locations: - SignalR DTOs → ViewModels (renamed Dto→ViewModel suffix) - Pipeline DTOs → Models/Pipelines - UserInfoDto → Models/Auth - DataUpdateDto → Models/Infrastructure