[FEATURE] Include alpha channels for HUD elements

[lilnarco]

What feature would you like to be added.

Currently, many color options within the client lack customizable transparency. Adding alpha channels to HUD elements can reduce perceived clutter while maintaining useful information on screen. Primarily, any text elements like FeatureList, FPS, Biome, Speed, etc.

Is your feature request related to a problem? Please describe.

No, just added customization.

Additional context

Transparency is already supported in client theme, but not elsewhere.

[FluorideHistorian]

im not sure if this is even possible i dont think the vanilla font renderer supports transparency at all and im not sure the custom one does