fix(command): combined unknown-target message; cover both go-to summary forms

- UX: unknown-target message now reads "don't know any direction or place
  called '...'" so direction typos (e.g. 'go nroth') make sense
- clarity: resolveVisited uses equalsIgnoreCase for id/name matching;
  add null-world guard comment pointing to CommandTestSupport
- Javadoc: note that 'to' filler word is stripped, making go-to forms equivalent
- tests: assert 'through the Hallway' in 3-node route; update unknown message
  assertion; add adjacentWalkUsesShortSummary covering the n==2 short-form path

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Semesterprojekt/src/main/java/thb/jeanluc/adventure/command/impl/GoCommand.java

@@ -18,7 +18,8 @@ import java.util.Optional;
  * Moves the player. {@code go <direction>} steps once to a connected room.
  * {@code go to <room>} auto-walks the shortest path (BFS) over already-visited
  * rooms, honouring locked exits and darkness. Usage: {@code go <direction>} or
- * {@code go to <room>}.
+ * {@code go to <room>}. The parser strips the filler word "to", so "go to
+ * &lt;room&gt;" and "go &lt;room&gt;" are equivalent.
  */
 public class GoCommand implements Command {
 
@@ -63,7 +64,7 @@ public class GoCommand implements Command {
         String name = String.join(" ", args).toLowerCase();
         Room target = resolveVisited(ctx, name);
         if (target == null) {
-            ctx.getIo().write("You don't know any place called '" + name + "'.");
+            ctx.getIo().write("You don't know any direction or place called '" + name + "'.");
             return;
         }
         Room start = ctx.getPlayer().getCurrentRoom();
@@ -90,6 +91,7 @@ public class GoCommand implements Command {
 
     /** Finds a visited room whose id or display name matches {@code name}. */
     private Room resolveVisited(GameContext ctx, String name) {
+        // the command test harness (CommandTestSupport) uses a null world; production always has one
         if (ctx.getWorld() == null) {
             return null;
         }
@@ -98,7 +100,7 @@ public class GoCommand implements Command {
             if (r == null) {
                 continue;
             }
-            if (id.equals(name) || r.getName().toLowerCase().equals(name)) {
+            if (id.equalsIgnoreCase(name) || r.getName().equalsIgnoreCase(name)) {
                 return r;
             }
         }

Semesterprojekt/src/test/java/thb/jeanluc/adventure/command/impl/GoCommandPathTest.java

@@ -51,6 +51,7 @@ class GoCommandPathTest {
         new GoCommand().execute(ctx, List.of("library"));
         assertThat(ctx.getPlayer().getCurrentRoom().getId()).isEqualTo("library");
         assertThat(out(ctx)).contains("make your way");
+        assertThat(out(ctx)).contains("through the Hallway");
     }
 
     @Test
@@ -66,7 +67,7 @@ class GoCommandPathTest {
         GameContext ctx = world(false, "Library");
         new GoCommand().execute(ctx, List.of("dungeon"));
         assertThat(ctx.getPlayer().getCurrentRoom().getId()).isEqualTo("kitchen");
-        assertThat(out(ctx)).contains("don't know any place called 'dungeon'");
+        assertThat(out(ctx)).contains("don't know any direction or place called 'dungeon'");
     }
 
     @Test
@@ -90,4 +91,13 @@ class GoCommandPathTest {
         new GoCommand().execute(ctx, List.of("north"));
         assertThat(ctx.getPlayer().getCurrentRoom().getId()).isEqualTo("hallway");
     }
+
+    @Test
+    void adjacentWalkUsesShortSummary() {
+        GameContext ctx = world(false, "Library");
+        new GoCommand().execute(ctx, List.of("hallway"));
+        assertThat(ctx.getPlayer().getCurrentRoom().getId()).isEqualTo("hallway");
+        assertThat(out(ctx)).contains("make your way from the Kitchen to the Hallway");
+        assertThat(out(ctx)).doesNotContain("through");
+    }
 }