fix(isMacStyle): in Java, & is a bit-wise AND operator, not a logical…

… AND operator

src/main/java/de/danielluedecke/zettelkasten/database/Settings.java

@@ -114,7 +114,7 @@ public class Settings {
 	 *         feel
 	 */
 	public boolean isMacStyle() {
-		return PlatformUtil.isMacOS() & getLookAndFeel().contains("Aqua");
+		return getLookAndFeel().contains("Aqua") && PlatformUtil.isMacOS();
 	}
 
 	public boolean isSeaGlass() {

src/test/java/de/danielluedecke/zettelkasten/database/SettingsTest.java

@@ -131,15 +131,15 @@ void MainDataFile_setMainDataFile_Success() throws IOException {
 	}
 
 	@Test
-	void isMacStyle_MacOSWithAquaLookAndFeel_ReturnsTrue() {
-		Settings settings = new Settings();
-		// Set up the environment to simulate macOS with Aqua look and feel
-		// For example:
-		// Mocking PlatformUtil to return true for isMacOS()
-		// Mocking getLookAndFeel() to return a value containing "Aqua"
-
-		assertTrue(settings.isMacStyle());
-	}
+        void isMacStyle_MacOSWithAquaLookAndFeel_ReturnsTrue() {
+            Settings settings = new Settings();
+
+            if (System.getProperty("os.name").toLowerCase().startsWith("mac os") == true) {
+                assertTrue(settings.isMacStyle());
+            } else {
+                assertFalse(settings.isMacStyle());
+            }
+        }
 
 	@Test
 	void loadSettings_FileNotFound_ReturnsFalse() {