Introduce ASP.NET Core Identity with Guid keys: add Microsoft.AspNetCore.Identity.EntityFrameworkCore and update EF packages to 10.0.6. Replace DbContext with IdentityDbContext<AppUser, IdentityRole<Guid>, Guid>, apply entity configurations and map Identity tables to custom names (Users, Roles, UserRoles, etc.).
Add AppUser model (IsAdmin, IsActive, MustChangePassword, CreatedAt, UpdatedAt) and AppUserConfiguration to enforce required properties and table name. Add IdentitySeedService to create an initial admin account if none exists and log results.
Add generated migration InitIdentity and update the DbContext model snapshot. Wire up Identity in Program.cs (identity options, cookie config, AddEntityFrameworkStores), enable structured console logging and HTTP request logging, run migrations on startup and call the seed service, and enable authentication/authorization middleware. Update codexInfo.md to document the logging and seeding changes.
Add PostgreSQL support and EF Core migrations for local development. Introduces ApplicationDbContext, adds Npgsql.EntityFrameworkCore.PostgreSQL and EF Core Design packages, and includes generated migrations (InitialPostgres and RemoveTestItems) plus updated model snapshot. Program.cs now loads an optional API/appsettings.custom.json, configures the DbContext from ConnectionStrings:Postgres and runs Database.Migrate() on startup. Adds a Dev docker-compose.yml to run postgres + pgAdmin, pins dotnet-ef in dotnet-tools.json, and adds ConnectionStrings to appsettings files. Also ignores API/appsettings.custom.json in .gitignore and updates README/codexInfo to document the new DB/dev workflow.
Jonas