fix(docker): update user creation for Ubuntu 24.04 base image (#368)

- Replace adduser with groupadd/useradd for Ubuntu compatibility
- Document base OS change from Debian 12 to Ubuntu 24.04 in CHANGELOG

Microsoft changed .NET 10 base images from Debian to Ubuntu,
requiring updated user creation commands. This ensures CD pipeline
builds successfully when publishing Docker images.

Author: nanotaboada

CHANGELOG.md

@@ -65,7 +65,8 @@ This project uses famous football stadiums (A-Z) that hosted FIFA World Cup matc
 - Update Microsoft.EntityFrameworkCore.Sqlite to 10.0.0
 - Update Microsoft.EntityFrameworkCore.Design to 10.0.0
 - Update Microsoft.VisualStudio.Web.CodeGeneration.Design to 10.0.0
-- Update Docker images to .NET 10 SDK and runtime
+- Update Docker images to .NET 10 SDK and runtime (now based on Ubuntu 24.04 LTS instead of Debian 12)
+- Update Dockerfile user creation commands for Ubuntu compatibility (`groupadd`/`useradd` instead of `adduser`)
 - Update CI/CD pipelines to use .NET 10 SDK
 - Token efficiency strategy for Copilot/AI agents with optimized instruction loading and improved token counting script (#364)
 - Bump Swashbuckle.AspNetCore from 10.1.0 to 10.1.2

Dockerfile

@@ -57,7 +57,7 @@ COPY --chmod=555        scripts/healthcheck.sh      ./healthcheck.sh
 COPY --from=builder /src/Dotnet.Samples.AspNetCore.WebApi/storage/players-sqlite3.db ./hold/players-sqlite3.db
 
 # Add non-root user and make volume mount point writable
-RUN adduser --system --disabled-password --group aspnetcore && \
+RUN groupadd -r aspnetcore && useradd -r -g aspnetcore aspnetcore && \
     mkdir -p /storage && \
     chown aspnetcore:aspnetcore /storage