Refactor Assets/Scripts: trim restating comments, minor structure cleanups

Sweep over 48 files (Editor/ excluded): remove comments that restate the
code, condense class summaries, fix three stale doc statements
(HsvColorPicker alpha bar, PaintHud layoutPrefab, MasterVolume
FallbackDefault). Inline two single-use wrappers (IsPointerOverUi,
BuildModes), drop an unused using, replace a magic literal with the
existing ParallaxBase constant, and convert ~10 UnityEngine.Object null
checks to the implicit-bool convention. No serialized fields, signatures,
RPC/NetworkVariable names, defaults, or #if blocks touched.

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

Assets/Scripts/GameMode/GameModeManager.cs

@@ -107,7 +107,7 @@ public class GameModeManager : MonoBehaviour
         if (!freeCam) freeCam = FindFirstObjectByType<FreeCamController>(FindObjectsInactive.Include);
         if (!firstPerson) firstPerson = FindFirstObjectByType<FirstPersonController>(FindObjectsInactive.Include);
 
-        BuildModes();
+        BuildModes(null);
     }
 
     private void Start()
@@ -125,8 +125,6 @@ public class GameModeManager : MonoBehaviour
     /// <summary>Registers the modes for the current context. Without a role (no networked avatar yet,
     /// or a non-networked scene) the full set is built from whichever rigs are present. With a role the
     /// set is scoped to that side and ordered so index 0 is its intended start mode. Add new modes here.</summary>
-    private void BuildModes() => BuildModes(null);
-
     private void BuildModes(PlayerRole? role)
     {
         _modes.Clear();
@@ -480,7 +478,7 @@ public class GameModeManager : MonoBehaviour
         for (int i = 0; i < avatars.Count; i++)
         {
             var avatar = avatars[i];
-            if (!avatar || avatar.IsOwner) continue; // skip the local player's own avatar
+            if (!avatar || avatar.IsOwner) continue;
             var col = avatar.BodyCollider;
             if (col && col.enabled) Physics.IgnoreCollision(capsule, col, ignore);
         }