Reducing usage of #if CLIENT / #elif SERVER

The server will implement some classes it probably shouldn't need because certain items or game states depend on them.

BarotraumaShared/Content/damageshader.fx

@@ -0,0 +1,38 @@
+
+Texture xTexture;
+sampler TextureSampler : register (s0) = sampler_state { Texture = <xTexture>; };
+
+Texture xStencil;
+sampler StencilSampler = sampler_state { Texture = <xStencil>; };
+
+
+float aCutoff;
+float aMultiplier;
+
+float cCutoff;
+float cMultiplier;
+
+float4 main(float4 position : SV_Position, float4 color : COLOR0, float2 texCoord : TEXCOORD0) : COLOR0
+{
+	float4 c = tex2D(TextureSampler, texCoord);
+
+	float4 stencilColor = tex2D(StencilSampler, texCoord);
+
+	float aDiff = stencilColor.a - aCutoff;
+
+	clip(aDiff);
+
+	float cDiff = stencilColor.a - cCutoff;
+
+	return float4(
+		lerp(stencilColor.rgb, c.rgb, clamp(cDiff * cMultiplier, 0.0f, 1.0f)),
+		min(aDiff * aMultiplier, c.a));
+}
+
+technique StencilShader
+{
+    pass Pass1
+    {
+        PixelShader = compile ps_4_0_level_9_3 main();
+    }
+}