Hotplate overhaul (#17586)

* Hotplate overhaul

- Beakers are now placed on top of the hotplate instead of itemslot.
- Hotplate LED now only lights up if it's heating something.
- More comments/xmldoc.
- Some other minor tweaks.

* Actually remove the beaker slot

Content.Server/Chemistry/Components/SolutionHeaterComponent.cs

@@ -1,19 +1,50 @@
-namespace Content.Server.Chemistry.Components;
+using Content.Shared.Whitelist;
+
+namespace Content.Server.Chemistry.Components;
 
 [RegisterComponent]
 public sealed class SolutionHeaterComponent : Component
 {
-    public readonly string BeakerSlotId = "beakerSlot";
-
-    [DataField("heatPerSecond")]
-    public float HeatPerSecond = 120;
+    /// <summary>
+    /// How much heat is added per second to the solution, with no upgrades.
+    /// </summary>
+    [DataField("baseHeatPerSecond")]
+    public float BaseHeatPerSecond = 120;
 
+    /// <summary>
+    /// How much heat is added per second to the solution, taking upgrades into account.
+    /// </summary>
     [ViewVariables(VVAccess.ReadWrite)]
-    public float HeatMultiplier = 1;
+    public float HeatPerSecond;
 
-    [DataField("machinePartHeatPerSecond")]
-    public string MachinePartHeatPerSecond = "Capacitor";
+    /// <summary>
+    /// The machine part that affects the heat multiplier.
+    /// </summary>
+    [DataField("machinePartHeatMultiplier")]
+    public string MachinePartHeatMultiplier = "Capacitor";
 
+    /// <summary>
+    /// How much each upgrade multiplies the heat by.
+    /// </summary>
     [DataField("partRatingHeatMultiplier")]
     public float PartRatingHeatMultiplier = 1.5f;
+
+    /// <summary>
+    /// The entities that are placed on the heater.
+    /// <summary>
+    [DataField("placedEntities")]
+    public HashSet<EntityUid> PlacedEntities = new();
+
+    /// <summary>
+    /// The max amount of entities that can be heated at the same time.
+    /// </summary>
+    [DataField("maxEntities")]
+    public uint MaxEntities = 1;
+
+    /// <summary>
+    /// Whitelist for entities that can be placed on the heater.
+    /// </summary>
+    [DataField("whitelist")]
+    [ViewVariables(VVAccess.ReadWrite)]
+    public EntityWhitelist? Whitelist;
 }