Power cell slot QOL (#15373)

Content.Server/PowerCell/PowerCellDrawComponent.cs

@@ -0,0 +1,25 @@
+namespace Content.Server.PowerCell;
+
+/// <summary>
+/// Indicates that the entity's ActivatableUI requires power or else it closes.
+/// </summary>
+[RegisterComponent]
+public sealed class PowerCellDrawComponent : Component
+{
+    [ViewVariables(VVAccess.ReadWrite), DataField("enabled")]
+    public bool Enabled = false;
+
+    /// <summary>
+    /// How much the entity draws while the UI is open.
+    /// Set to 0 if you just wish to check for power upon opening the UI.
+    /// </summary>
+    [ViewVariables(VVAccess.ReadWrite), DataField("drawRate")]
+    public float DrawRate = 1f;
+
+    /// <summary>
+    /// How much power is used whenever the entity is "used".
+    /// This is used to ensure the UI won't open again without a minimum use power.
+    /// </summary>
+    [ViewVariables(VVAccess.ReadWrite), DataField("useRate")]
+    public float UseRate = 0f;
+}