Add a transparency setting to the "Disabled Rendering" boxes

[periapsises]

This adds a settings for users to control the transparency of the boxes that are visible when rendering is disabled.
The default is set to 0.05 and can be modified either through the client convar prop2mesh_disabled_transparency or through a slider below the checkbox for disabling rendering:

There is also a server managed convar to allow or disallow the use of transparency on the server named serverAllowsTransparency which allows it by default.
Useful to prevent players from seeing internal components on things like ACF servers.

Note

Changing this setting requires a map change or server restart to take effect.

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Here is a comparision of how that looks in game.

Before:

After: