fix(B.6+B.7): re-send action on local arrival; scale indicator box by entity Scale

User report: 'It still however just approach it and does not use it.'
Root cause: local auto-walk arrives at the target visually, but ACE's
server-side MoveToChain may have timed out before our position was
recognised as in-range (we don't echo authoritative position back to
ACE during the walk yet). The action never fires.

Fix (re-send on arrival):
  * PlayerMovementController.AutoWalkArrived event fires once when
    EndServerAutoWalk(reason='arrived') is called.
  * GameWindow tracks _pendingPostArrivalAction = (guid, isPickup)
    on each SendUse / SendPickUp.
  * OnAutoWalkArrivedReSendAction (subscribed at EnterPlayerModeNow)
    re-sends the action with isRetryAfterArrival=true. The retry
    flag prevents the re-sent action from itself setting a new
    pending action — breaks any potential re-fire loop.
  * The re-sent action is close-range from the local body's
    perspective, so ACE's CreateMoveToChain hits the WithinUseRadius
    shortcut (Player_Move.cs:66) and completes immediately —
    dialogue opens, item picks up.

User report: 'items dropped on the ground now have a smaller triangle
box, perhaps too small. Also now other stuff like signs also have a
very small triangle box, should not have it should scale to the size
of the object.'

Fix (scale-aware indicator height):
  * TargetIndicatorPanel.TargetInfo now carries entity Scale.
  * EntityHeightFor multiplies the per-type base by Scale so an
    upscaled NPC / sign / lifestone gets a proportionally larger box.
  * Per-type table refined:
      Creature                    : 1.8 m * scale
      Door/Lifestone/Portal       : 2.4 m * scale
      Small carry items (weapon/armor/clothing/jewelry/food/money/
        misc/missile-weapon/container/gem/spellcomp/writable/key/
        caster — most pickup-able): 0.8 m * scale  (up from 0.5 m)
      Everything else (signs / scenery interactables / untyped):
        1.5 m * scale  (up from 0.5 m default)

Deferred to follow-up: exact mesh-AABB-derived box (need to read
each entity's actual rendered bounds at registration time).

src/AcDream.App/Input/PlayerMovementController.cs

@@ -250,6 +250,23 @@ public sealed class PlayerMovementController
     /// </summary>
     public bool IsServerAutoWalking => _autoWalkActive;
 
+    /// <summary>
+    /// Fires once when an auto-walk reaches its destination naturally
+    /// (i.e. <see cref="EndServerAutoWalk"/> called with
+    /// <c>reason="arrived"</c>). Does NOT fire on user-input cancel or
+    /// on a re-target (BeginServerAutoWalk overwriting state).
+    ///
+    /// <para>
+    /// Host (<see cref="Rendering.GameWindow"/>) subscribes to re-send
+    /// the Use/PickUp action that triggered the auto-walk — without
+    /// this, ACE's server-side MoveToChain may have already timed out
+    /// by the time our local body arrives, so the action wouldn't
+    /// fire. Re-sending the action close-range hits ACE's WithinUseRadius
+    /// fast-path and completes immediately.
+    /// </para>
+    /// </summary>
+    public event Action? AutoWalkArrived;
+
     public PlayerMovementController(PhysicsEngine physics)
     {
         _physics = physics;
@@ -384,6 +401,8 @@ public sealed class PlayerMovementController
         _autoWalkActive = false;
         if (PhysicsDiagnostics.ProbeAutoWalkEnabled)
             Console.WriteLine($"[autowalk-end] reason={reason}");
+        if (reason == "arrived")
+            AutoWalkArrived?.Invoke();
     }
 
     /// <summary>