feat(io): RoomView/Hud views and default Renderings

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Semesterprojekt/src/test/java/thb/jeanluc/adventure/io/text/RenderingsTest.java

@@ -0,0 +1,38 @@
+package thb.jeanluc.adventure.io.text;
+
+import org.junit.jupiter.api.Test;
+import java.util.List;
+import static org.assertj.core.api.Assertions.assertThat;
+
+class RenderingsTest {
+
+    @Test
+    void roomToStyledText_includesNameDescriptionItemsNpcsExits() {
+        RoomView room = new RoomView("Kitchen", "A cold kitchen.",
+                List.of("Lamp", "Letter"), List.of("Old Man"), List.of("north", "east"));
+
+        String text = Renderings.roomToStyledText(room).plainText();
+
+        assertThat(text).contains("Kitchen");
+        assertThat(text).contains("A cold kitchen.");
+        assertThat(text).contains("Lamp").contains("Letter");
+        assertThat(text).contains("Old Man");
+        assertThat(text).contains("north").contains("east");
+    }
+
+    @Test
+    void roomToStyledText_noExits_saysNoObviousExits() {
+        RoomView room = new RoomView("Void", "Nothing.", List.of(), List.of(), List.of());
+        assertThat(Renderings.roomToStyledText(room).plainText())
+                .contains("no obvious exits");
+    }
+
+    @Test
+    void roomToStyledText_tagsItemSpansWithItemStyle() {
+        RoomView room = new RoomView("Kitchen", "desc",
+                List.of("Lamp"), List.of(), List.of("north"));
+        boolean hasItemSpan = Renderings.roomToStyledText(room).spans().stream()
+                .anyMatch(s -> s.style() == Style.ITEM && s.text().equals("Lamp"));
+        assertThat(hasItemSpan).isTrue();
+    }
+}