[Entity] Brig Timers (#15285)

* brigtimer

* ok

* TextScreen w timer implementation

* second commit

* working brig timer

* signal timers near completion

* soon done

* removed licenses, fixes noRotation on screens, minor edits

* no message

* no message

* removed my last todos

* removed csproj.rej??

* missed a thing with .yml and tests

* fix tests

* Update base_structureairlocks.yml

* timespan type serialize

* activation turned into comp

* sloth review

* Update timer.yml

* small changes

---------

Co-authored-by: CommieFlowers <rasmus.cedergren@hotmail.com>
Co-authored-by: rolfero <45628623+rolfero@users.noreply.github.com>

Content.Shared/TextScreen/TextScreenVisuals.cs

@@ -0,0 +1,35 @@
+using Robust.Shared.Serialization;
+
+namespace Content.Shared.TextScreen;
+
+[Serializable, NetSerializable]
+public enum TextScreenVisuals : byte
+{
+    /// <summary>
+    ///     Should this show any text? <br/>
+    ///     Expects a <see cref="bool"/>.
+    /// </summary>
+    On,
+    /// <summary>
+    ///     Is this a timer or a text-screen? <br/>
+    ///     Expects a <see cref="TextScreenMode"/>.
+    /// </summary>
+    Mode,
+    /// <summary>
+    ///     What text to show? <br/>
+    ///     Expects a <see cref="string"/>.
+    /// </summary>
+    ScreenText,
+    /// <summary>
+    ///     What is the target time? <br/>
+    ///     Expects a <see cref="TimeSpan"/>.
+    /// </summary>
+    TargetTime
+}
+
+[Serializable, NetSerializable]
+public enum TextScreenMode : byte
+{
+    Text,
+    Timer
+}