ci: add validate file encoding and min version update

Signed-off-by: Jeremy Andrews <[email protected]>

.github/workflows/validation-workflow.yml

@@ -84,6 +84,26 @@ jobs:
             echo "✅ All developer-made commit messages follow the convention."
           fi
 
+  validate-file-encoding:
+    name: Validate File Encoding
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout Repository
+        uses: actions/checkout@v4
+
+      - name: Validate File Encoding
+        run: |
+          echo "Validating file encoding..."
+          NON_UTF8_FILES=$(find . -type f -exec file -i {} + | grep -v "charset=utf-8" || true)
+
+          if [ -n "$NON_UTF8_FILES" ]; then
+            echo "❌ The following files are not UTF-8 encoded:"
+            echo "$NON_UTF8_FILES"
+            exit 1
+          else
+            echo "✅ All files are UTF-8 encoded."
+          fi
+
   validate-dart-sdk-version:
     runs-on: ubuntu-latest
     steps:
@@ -100,7 +120,7 @@ jobs:
           echo "$PUBSPEC_FILES"
 
           # Define the minimum required Dart SDK version
-          MINIMUM_VERSION="3.5.4"
+          MINIMUM_VERSION="3.6.0"
           ALL_VALID="true"
 
           # Iterate over each pubspec.yaml file