Hygiene B6b: convert leaky-world tests + HudSystem cosmetics

- 10 EditMode files: every bare trailing world.Dispose() now inside using(world){} (single-world) or a [TearDown]+List<World> (the multi-world reject-matrix tests in BoonApplyTests/RouteSelectSystemTests) — an assertion failure can no longer leak the World and mask the true first failure. No test logic changed.
- HudSystem: collapse the blank-line run before the class close; trim the extracted route-map clause from the READY-panel comment.

466/466 EditMode tests pass.

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

Assets/_Project/Tests/EditMode/RunRosterRegressionTests.cs

@@ -55,6 +55,8 @@ namespace ProjectM.Tests
         public void StalePendingAtBase_DoesNotHoldGate_AndIsStrippedOnExit()
         {
             var (world, group, dir) = MakeWorld(out var map);
+            using (world)
+            {
             var em = world.EntityManager;
             em.SetComponentData(dir, new RunInfo
             {
@@ -86,13 +88,15 @@ namespace ProjectM.Tests
             Assert.AreEqual(0, em.GetComponentData<BoonOffer>(alive).Pending,
                 "no offer survives the gate");
 
-            world.Dispose();
+            }
         }
 
         [Test]
         public void Advance_TeleportsOnlyParticipants_LateJoinerStaysAtBase()
         {
             var (world, group, dir) = MakeWorld(out var map);
+            using (world)
+            {
             var em = world.EntityManager;
             em.SetComponentData(dir, new RunInfo
             {
@@ -130,7 +134,7 @@ namespace ProjectM.Tests
             Assert.AreEqual(RegionId.Base, em.GetComponentData<RegionTag>(lateJoiner).Region,
                 "the late joiner stays in the Base relevancy bucket");
 
-            world.Dispose();
+            }
         }
     }
 }