Reduced Warning Count By 130 For Full Rebuilds (#26518)

* remove deprecated entity coordinate extension functions. Reduces warning count by approximately 50

* final toCoords Removed

* Remove all unused variables and dead code paths

* remove always true variable, should be a cvar or something instead

* remove superfluous variables from tests

(cherry picked from commit 59e46aab93)

Content.Server/Power/EntitySystems/ExtensionCableSystem.cs

@@ -1,6 +1,5 @@
 using System.Diagnostics.CodeAnalysis;
 using Content.Server.Power.Components;
-using Robust.Shared.Map;
 using Robust.Shared.Map.Components;
 using Robust.Shared.Physics;
 using Robust.Shared.Physics.Components;
@@ -9,8 +8,6 @@ namespace Content.Server.Power.EntitySystems
 {
     public sealed class ExtensionCableSystem : EntitySystem
     {
-        [Dependency] private readonly IMapManager _mapManager = default!;
-
         public override void Initialize()
         {
             base.Initialize();