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/MetaSeedingTests.cs

@@ -67,6 +67,8 @@ namespace ProjectM.Tests
         public void Spawn_SeedsClassTiers_SkipsOthers_ClampsOverMax()
         {
             var (world, group) = MakeWorld();
+            using (world)
+            {
             var em = world.EntityManager;
             var prefab = MakePlayerPrefab(em);
             var spawnerE = em.CreateEntity(typeof(PlayerSpawner));
@@ -104,13 +106,15 @@ namespace ProjectM.Tests
             Assert.AreEqual(2, metaRows, "exactly the two legal Warrior tiers seeded (unknown/other-class/other-mask skipped)");
             Assert.AreEqual(30f, frameValue, 1e-3f, "Reinforced Frame tier 2 = 15 * 2");
             Assert.AreEqual(0.40f, mightValue, 1e-3f, "Warrior's Might CLAMPED to MaxTier 4 = 0.10 * 4 (D-F5)");
-            world.Dispose();
+            }
         }
 
         [Test]
         public void MissingCatalog_BlocksSpawn_PreservesRequest()
         {
             var (world, group) = MakeWorld();
+            using (world)
+            {
             var em = world.EntityManager;
             var prefab = MakePlayerPrefab(em);
             var spawnerE = em.CreateEntity(typeof(PlayerSpawner));
@@ -125,7 +129,7 @@ namespace ProjectM.Tests
             var rq = em.CreateEntityQuery(typeof(GoInGameRequest));
             Assert.AreEqual(1, rq.CalculateEntityCount(), "request PRESERVED — the spawn retries when the catalog streams in");
             pq.Dispose(); rq.Dispose(); // BEFORE the world (a using-var here would outlive it)in");
-            world.Dispose();
+            }
         }
     }
 }