implement entities, dto, mediart, validators, tests for art templates…#276

InnetaSh merged 16 commits into

devproject-studying-dotnet/Streetcode-Server-May2026:devfrom

task/274/Implement-backend-functionality-for-Art-Galleryproject-studying-dotnet/Streetcode-Server-May2026:task/274/Implement-backend-functionality-for-Art-GalleryCopy head branch name to clipboard