Checkpoint: pre-realignment working tree (Gym->GymSub repoint + SyntyWorld/PostFX re-enable, SampleScene removed, PostFX_Daylight retune, ai.assistant pkg re-added)

Baseline before the LANTERN realignment & purge (plan: one look, four scenes,
Bathynaut on the player). Gym.unity edits are operator-made in-editor.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Assets/Scenes/Gym.unity

@@ -708,7 +708,7 @@ GameObject:
   m_Icon: {fileID: 0}
   m_NavMeshLayer: 0
   m_StaticEditorFlags: 0
-  m_IsActive: 0
+  m_IsActive: 1
 --- !u!114 &228729545
 MonoBehaviour:
   m_ObjectHideFlags: 0
@@ -1183,6 +1183,7 @@ MonoBehaviour:
   FollowSharpness: 8
   FallbackTarget: {x: 3, y: 0, z: 4}
   AimLeadDistance: 2.5
+  LeadSharpness: 3
 --- !u!4 &331593291 stripped
 Transform:
   m_CorrespondingSourceObject: {fileID: 4855556370681302, guid: 65f76c5f923964045833f09a3f767a16, type: 3}
@@ -3100,6 +3101,8 @@ MonoBehaviour:
   Hit: {fileID: 1854123508608598, guid: 6225eb3558e891443a80232b18635a69, type: 3}
   EnemyDeath: {fileID: 6581819978879567992, guid: f32c52b21351a7d4e86f68f722682e2d, type: 3}
   PlayerDeath: {fileID: 6581819978879567992, guid: bc83be4333d697447b9d63083553524d, type: 3}
+  Portal: {fileID: 0}
+  EnemySpawn: {fileID: 0}
 --- !u!4 &1116745582
 Transform:
   m_ObjectHideFlags: 0
@@ -3397,10 +3400,10 @@ MonoBehaviour:
   AutoLoadScene: 1
   _SceneGUID:
     Value:
-      x: 3807153369
-      y: 2538014340
-      z: 2171413394
-      w: 557737884
+      x: 1458338902
+      y: 1245977915
+      z: 4149519749
+      w: 869787926
 --- !u!4 &1314640900
 Transform:
   m_ObjectHideFlags: 0
@@ -4151,7 +4154,7 @@ GameObject:
   m_Icon: {fileID: 0}
   m_NavMeshLayer: 0
   m_StaticEditorFlags: 0
-  m_IsActive: 0
+  m_IsActive: 1
 --- !u!4 &1736670160
 Transform:
   m_ObjectHideFlags: 0

Assets/Scenes/SampleScene.unity.meta

@@ -1,7 +0,0 @@
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-DefaultImporter:
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-  userData: 
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