Codex/UI color palette

[bodhibuurstede-sys]

Summary

PR checklist

• The game builds properly without errors.

• No unrelated changes are present.

• No "trash" files are committed.

• Relevant code is documented.

• Update the related GitBook document, or create a new one if needed.

Pictures/Videos

Testing

Networking checklist

• Works from host in host mode.

• Works from server in server mode.

• Works on server in client mode.

• Works and is syncronized across different clients.

• Is persistent.

Changes

Related issues/PRs

[bodhibuurstede-sys]

Quick context for reviewers:

Summary

This PR adds a centralized UI color palette for shared SS3D interface colors.

It expands PaletteColors from a few loose static fields into an enum-backed palette that can be fetched by semantic key, enumerated by tools, and extended in one place. It also adds documentation for how to use the palette in UI code.

Changes

• Added PaletteColor, PaletteColorDefinition, and lookup helpers to Assets/Scripts/SS3D/Data/PaletteColors.cs.
• Added existing generic button overlay/text colors to the shared palette.
• Kept the existing direct static color fields available for current callers.
• Added Documents/UI_COLOR_PALETTE.md with usage guidance and extension steps.
• Switched existing byte-style RGB palette values to Color32, since Unity's Color constructor expects normalized 0f..1f channels.

Testing

Not run locally. I do not have a Unity environment available in this Codex session, so this change was reviewed statically only.

Addresses #1377.