More PA fixes (#18131)

If the PA Control Box isn't rotated to match the Fuel Chamber, it actually rotates itself to match.

This rotation triggered a rotation event, which in turn caused RescanParts() to run again, re-entrantly. This broke everything.

Fixed by adding a boolean to just guard against this.

Content.Server/ParticleAccelerator/Components/ParticleAcceleratorControlBoxComponent.cs

@@ -39,6 +39,12 @@ public sealed class ParticleAcceleratorControlBoxComponent : Component
     [ViewVariables]
     public bool Firing = false;
 
+    /// <summary>
+    /// Block re-entrant rescanning.
+    /// </summary>
+    [ViewVariables(VVAccess.ReadWrite)]
+    public bool CurrentlyRescanning = false;
+
     /// <summary>
     /// Whether the PA is currently firing or charging to fire.
     /// Bounded by <see cref="ParticleAcceleratorPowerState.Standby"/> and <see cref="MaxStrength"/>.