Fixes #4374 - Nukes all (?) legacy Driver and Application stuff; revamps tests (#4376)

.github/workflows/build-validation.yml

@@ -0,0 +1,58 @@
+name: Build Validation
+
+on:
+  push:
+    branches: [ v2_release, v2_develop ]
+    paths-ignore:
+      - '**.md'
+  pull_request:
+    branches: [ v2_release, v2_develop ]
+    paths-ignore:
+      - '**.md'
+      
+jobs:
+  build-validation:
+    name: Build All Configurations
+    runs-on: ubuntu-latest
+    
+    timeout-minutes: 10
+    steps:
+
+    - name: Checkout code
+      uses: actions/checkout@v4
+
+    - name: Setup .NET Core
+      uses: actions/setup-dotnet@v4
+      with:
+        dotnet-version: 8.x
+        dotnet-quality: 'ga'
+
+    - name: Restore dependencies
+      run: dotnet restore
+
+    # Suppress CS0618 (member is obsolete) and CS0612 (member is obsolete without message)
+    # Using -property: syntax with URL-encoded semicolon (%3B) to avoid shell interpretation issues
+    - name: Build Debug
+      run: dotnet build --configuration Debug --no-restore -property:NoWarn=0618%3B0612
+
+    - name: Build Release Terminal.Gui
+      run: dotnet build Terminal.Gui/Terminal.Gui.csproj --configuration Release --no-incremental --force -property:NoWarn=0618%3B0612
+
+    - name: Pack Release Terminal.Gui
+      run: dotnet pack Terminal.Gui/Terminal.Gui.csproj --configuration Release --output ./local_packages -property:NoWarn=0618%3B0612
+
+    - name: Restore AOT and Self-Contained projects
+      run: |
+        dotnet restore ./Examples/NativeAot/NativeAot.csproj -f
+        dotnet restore ./Examples/SelfContained/SelfContained.csproj -f
+
+    - name: Restore Solution Packages
+      run: dotnet restore
+
+    - name: Build Release AOT and Self-Contained
+      run: |
+        dotnet build ./Examples/NativeAot/NativeAot.csproj --configuration Release -property:NoWarn=0618%3B0612
+        dotnet build ./Examples/SelfContained/SelfContained.csproj --configuration Release -property:NoWarn=0618%3B0612
+
+    - name: Build Release Solution
+      run: dotnet build --configuration Release --no-restore -property:NoWarn=0618%3B0612