PUT /api/routes/{id}/region assigns/reassigns an existing route to a
region directly, validating the target region exists and is active.
Stands in for the blocked assignAreaToRegion until an Area entity
exists between Region and Route.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Added .gitignore, solution, and project files for .NET 10. Introduced AGENTS.md and PLAN.md for guidelines and planning. Implemented appsettings.json, launchSettings.json, and MySQL config. Created AppDBContext and all domain models with composite keys. Added IUnitOfWork and EFUnitOfWork. Structured feature folders for Region, Route, Vehicle, Store, Warehouse, and Order with DTOs, repositories, services, and controllers. Added initial EF Core migrations and sample HTTP request. Registered dependencies and enabled OpenAPI in development.