Fix GitHub Actions build issues and add Docker testing

Workflow fixes:
- Remove non-existent qtnetwork5-dev package from Linux build
- Remove invalid Qt5 modules from Windows build (qtmultimedia/qtnetwork are included in base)
- Fix package names for Ubuntu 20.04 compatibility

Docker testing tools:
- Add Dockerfile.ubuntu for local Linux build testing
- Add test-linux-build.sh script for podman/docker testing
- Enables debugging build issues locally before pushing

These fixes address the package installation failures in both
Windows and Linux GitHub Actions workflows.

Author: pedgarcia

.github/workflows/build-linux.yml

@@ -68,8 +68,8 @@ jobs:
           qt5-default \
           qtbase5-dev \
           qtmultimedia5-dev \
-          qtnetwork5-dev \
-          libqt5multimedia5-plugins
+          libqt5multimedia5-plugins \
+          libqt5network5
 
     - name: Install additional packaging tools
       run: |

.github/workflows/build-windows.yml

@@ -32,7 +32,8 @@ jobs:
         host: 'windows'
         target: 'desktop'
         arch: 'win64_msvc2019_64'
-        modules: 'qtmultimedia qtnetwork'
+        # Note: qtmultimedia and qtnetwork are included in base Qt5 installation
+        # modules: 'qtmultimedia qtnetwork'  # These aren't separate modules in 5.15.2
         setup-python: 'false'
 
     - name: Setup MSVC

docker/Dockerfile.ubuntu

@@ -0,0 +1,68 @@
+# Dockerfile for testing Linux build locally
+# Based on Ubuntu 20.04 LTS (same as GitHub Actions)
+
+FROM ubuntu:20.04
+
+# Prevent interactive prompts during package installation
+ENV DEBIAN_FRONTEND=noninteractive
+ENV TZ=UTC
+
+# Install system dependencies (same as GitHub Actions workflow)
+RUN apt-get update && apt-get install -y \
+    build-essential \
+    cmake \
+    git \
+    pkg-config \
+    libtool \
+    autoconf \
+    automake \
+    libgl1-mesa-dev \
+    libglu1-mesa-dev \
+    libxrandr-dev \
+    libxss-dev \
+    libxcursor-dev \
+    libxinerama-dev \
+    libxi-dev \
+    libxext-dev \
+    libxfixes-dev \
+    libxrender-dev \
+    libxcb1-dev \
+    libx11-xcb-dev \
+    libxcb-glx0-dev \
+    libfontconfig1-dev \
+    libfreetype6-dev \
+    libxcb-dri2-0-dev \
+    libxcb-dri3-dev \
+    libxcb-present-dev \
+    libxcb-sync-dev \
+    libxshmfence-dev \
+    libasound2-dev \
+    libpulse-dev \
+    file \
+    wget \
+    fuse \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install Qt5 (same as workflow)
+RUN apt-get update && apt-get install -y \
+    qt5-default \
+    qtbase5-dev \
+    qtmultimedia5-dev \
+    libqt5multimedia5-plugins \
+    libqt5network5 \
+    && rm -rf /var/lib/apt/lists/*
+
+# Install packaging tools
+RUN apt-get update && apt-get install -y \
+    dpkg-dev \
+    fakeroot \
+    && rm -rf /var/lib/apt/lists/*
+
+# Set up working directory
+WORKDIR /workspace
+
+# Copy source code (will be mounted)
+# COPY . .
+
+# Default command
+CMD ["/bin/bash"]

docker/test-linux-build.sh

@@ -0,0 +1,84 @@
+#!/bin/bash
+#
+# test-linux-build.sh - Test Linux build locally using Docker
+#
+# This script builds a Docker container matching the GitHub Actions Linux
+# environment and tests the build process locally for debugging.
+#
+
+set -e
+
+SCRIPT_DIR="$(cd "$(dirname "$0")" && pwd)"
+PROJECT_ROOT="$(dirname "$SCRIPT_DIR")"
+
+echo "=== Testing Linux Build with Docker ==="
+echo "Project root: $PROJECT_ROOT"
+
+# Build container image with podman
+echo "Building container image with podman..."
+podman build -t fujisan-linux-test -f "$SCRIPT_DIR/Dockerfile.ubuntu" "$SCRIPT_DIR"
+
+# Run the build in container
+echo "Running Linux build test..."
+podman run --rm \
+    -v "$PROJECT_ROOT:/workspace" \
+    -w /workspace \
+    -e FUJISAN_VERSION="v1.0.0-test" \
+    fujisan-linux-test \
+    bash -c '
+        echo "=== Docker Environment Info ==="
+        echo "OS: $(cat /etc/os-release | grep PRETTY_NAME)"
+        echo "CMAKE: $(cmake --version | head -1)"
+        echo "Qt5: $(qmake -query QT_VERSION)"
+        echo "GCC: $(gcc --version | head -1)"
+        echo ""
+        
+        echo "=== Starting Build Process ==="
+        
+        # Create build directory
+        mkdir -p build-release
+        cd build-release
+        
+        # Configure CMake (this should download and build libatari800)
+        echo "Configuring CMake..."
+        cmake -DCMAKE_BUILD_TYPE=Release \
+              -DCMAKE_INSTALL_PREFIX=/usr \
+              -DFUJISAN_VERSION="${FUJISAN_VERSION:-dev}" \
+              ..
+        
+        echo "Building Fujisan..."
+        make -j$(nproc)
+        
+        # Verify libatari800 integration
+        echo "=== Verifying Build Results ==="
+        if [ -f "atari800-src/src/libatari800.a" ]; then
+            echo "✓ libatari800.a found and integrated"
+            ls -lh atari800-src/src/libatari800.a
+        else
+            echo "❌ libatari800.a not found"
+            echo "Looking for libatari800 files:"
+            find . -name "*libatari800*" -o -name "*atari800*" | head -10
+            exit 1
+        fi
+        
+        # Test binary
+        echo "Testing Fujisan binary..."
+        if [ -f "Fujisan" ]; then
+            echo "✓ Fujisan binary created"
+            ldd Fujisan | head -10
+            file Fujisan
+            ./Fujisan --help || echo "(Help command may not be available)"
+        else
+            echo "❌ Fujisan binary not found"
+            ls -la
+            exit 1
+        fi
+        
+        echo ""
+        echo "=== Build Test Completed Successfully! ==="
+    '
+
+echo ""
+echo "=== Docker Build Test Summary ==="
+echo "If the build completed successfully, the Linux workflow should work."
+echo "If there were errors, we can debug them locally before pushing fixes."