Combine solution injection systems; Fix embeddable injectors (#26268)

* Combine injection systems

* Update Content.Server/Chemistry/EntitySystems/SolutionInjectOnEventSystem.cs

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Co-authored-by: metalgearsloth <31366439+metalgearsloth@users.noreply.github.com>

Content.Server/Chemistry/Components/SolutionInjectOnEmbedComponent.cs

@@ -0,0 +1,8 @@
+namespace Content.Server.Chemistry.Components;
+
+/// <summary>
+/// Used for embeddable entities that should try to inject a
+/// contained solution into a target when they become embedded in it.
+/// </summary>
+[RegisterComponent]
+public sealed partial class SolutionInjectOnEmbedComponent : BaseSolutionInjectOnEventComponent { }