Feature/Move theme system from core to client-side ThemeProvider (#4108)

**Add approved & assigned issue number here:** 

Resolves #2549

## Description:

Themes are purely for the client's rendering, and the server doesn't
need context on them. This PR moves `Theme.ts` from
`src/core/configuration` to `src/client/theme` and moves affiliation
colors to `render-settings.json`.

This is to support the ability to add additional themes more quickly,
such as colorblind-friendly themes. No visible changes occur from this
refactor.

## Please complete the following:

- [X] I have added screenshots for all UI updates
- [X] I process any text displayed to the user through translateText()
and I've added it to the en.json file
- [X] I have added relevant tests to the test directory

## Please put your Discord username so you can be contacted if a bug or
regression is found:

jetaviz

---------

Co-authored-by: Josh Harris <josh@wickedsick.com>

src/client/render/gl/RenderSettings.ts

@@ -79,6 +79,27 @@ export interface RenderSettings {
     defensePostRange: number;
     embargoTintRatio: number;
     friendlyTintRatio: number;
+    embargoTintR: number;
+    embargoTintG: number;
+    embargoTintB: number;
+    friendlyTintR: number;
+    friendlyTintG: number;
+    friendlyTintB: number;
+  };
+  /** Alt-view affiliation colors (0–1 RGB). */
+  affiliation: {
+    selfR: number;
+    selfG: number;
+    selfB: number;
+    allyR: number;
+    allyG: number;
+    allyB: number;
+    neutralR: number;
+    neutralG: number;
+    neutralB: number;
+    enemyR: number;
+    enemyG: number;
+    enemyB: number;
   };
   railroad: {
     railMinZoom: number;

src/client/render/gl/Renderer.ts

@@ -478,7 +478,7 @@ export class GPURenderer {
     this.sceneTarget = { fbo: sceneFbo, tex: sceneTex, w: 1, h: 1 };
 
     // --- Alt-view passes ---
-    this.affiliationPalette = new AffiliationPalette(gl);
+    this.affiliationPalette = new AffiliationPalette(gl, this.settings);
     const affTex = this.affiliationPalette.getTexture();
     this.borderStampPass.setAffiliationTex(affTex);
     this.unitPass.setAffiliationTex(affTex);

src/client/render/gl/passes/BorderStampPass.ts

@@ -27,6 +27,8 @@ export class BorderStampPass {
   private uDefenseCheckerDarken: WebGLUniformLocation;
   private uEmbargoTintRatio: WebGLUniformLocation;
   private uFriendlyTintRatio: WebGLUniformLocation;
+  private uEmbargoTint: WebGLUniformLocation;
+  private uFriendlyTint: WebGLUniformLocation;
   private uAltView: WebGLUniformLocation;
 
   private vao: WebGLVertexArrayObject;
@@ -79,6 +81,8 @@ export class BorderStampPass {
       this.program,
       "uFriendlyTintRatio",
     )!;
+    this.uEmbargoTint = gl.getUniformLocation(this.program, "uEmbargoTint")!;
+    this.uFriendlyTint = gl.getUniformLocation(this.program, "uFriendlyTint")!;
     this.uAltView = gl.getUniformLocation(this.program, "uAltView")!;
 
     gl.useProgram(this.program);
@@ -109,6 +113,18 @@ export class BorderStampPass {
     gl.uniform1f(this.uDefenseCheckerDarken, mo.defenseCheckerDarken);
     gl.uniform1f(this.uEmbargoTintRatio, mo.embargoTintRatio);
     gl.uniform1f(this.uFriendlyTintRatio, mo.friendlyTintRatio);
+    gl.uniform3f(
+      this.uEmbargoTint,
+      mo.embargoTintR,
+      mo.embargoTintG,
+      mo.embargoTintB,
+    );
+    gl.uniform3f(
+      this.uFriendlyTint,
+      mo.friendlyTintR,
+      mo.friendlyTintG,
+      mo.friendlyTintB,
+    );
     gl.uniform1i(this.uAltView, this.altView ? 1 : 0);
 
     gl.activeTexture(gl.TEXTURE0);

src/client/render/gl/render-settings.json

@@ -75,7 +75,27 @@
     "highlightThicken": 2,
     "defensePostRange": 30,
     "embargoTintRatio": 0.35,
-    "friendlyTintRatio": 0.35
+    "friendlyTintRatio": 0.35,
+    "embargoTintR": 1,
+    "embargoTintG": 0,
+    "embargoTintB": 0,
+    "friendlyTintR": 0,
+    "friendlyTintG": 1,
+    "friendlyTintB": 0
+  },
+  "affiliation": {
+    "selfR": 0,
+    "selfG": 1,
+    "selfB": 0,
+    "allyR": 1,
+    "allyG": 1,
+    "allyB": 0,
+    "neutralR": 0.502,
+    "neutralG": 0.502,
+    "neutralB": 0.502,
+    "enemyR": 1,
+    "enemyG": 0,
+    "enemyB": 0
   },
   "railroad": {
     "railMinZoom": 4,

src/client/render/gl/shaders/day-night/border-stamp.frag.glsl

@@ -12,6 +12,8 @@ uniform float uHighlightBrighten;
 uniform float uDefenseCheckerDarken;
 uniform float uEmbargoTintRatio;
 uniform float uFriendlyTintRatio;
+uniform vec3 uEmbargoTint;
+uniform vec3 uFriendlyTint;
 
 in vec2 vWorldPos;
 out vec4 fragColor;
@@ -46,9 +48,9 @@ void main() {
       }
       // Relationship tint (applied BEFORE defense checkerboard, matching game)
       if (relation > 0.75) {
-        bc = mix(bc, vec3(1.0, 0.0, 0.0), uEmbargoTintRatio);
+        bc = mix(bc, uEmbargoTint, uEmbargoTintRatio);
       } else if (relation > 0.25) {
-        bc = mix(bc, vec3(0.0, 1.0, 0.0), uFriendlyTintRatio);
+        bc = mix(bc, uFriendlyTint, uFriendlyTintRatio);
       }
       // Defense bonus: checkerboard darken (applied AFTER tint, matching game)
       if (defense) {

src/client/render/gl/utils/Affiliation.ts

@@ -8,6 +8,7 @@
  * Rebuilt when localPlayerID or relationship data changes.
  */
 
+import type { RenderSettings } from "../RenderSettings";
 import { getPaletteSize } from "./ColorUtils";
 import { createTexture2D } from "./GlUtils";
 
@@ -16,20 +17,6 @@ const RELATION_NEUTRAL = 0;
 const RELATION_FRIENDLY = 1;
 const RELATION_EMBARGO = 2;
 
-// Affiliation RGB values (upstream PastelTheme)
-const SELF_R = 0,
-  SELF_G = 255,
-  SELF_B = 0;
-const ALLY_R = 255,
-  ALLY_G = 255,
-  ALLY_B = 0;
-const NEUTRAL_R = 128,
-  NEUTRAL_G = 128,
-  NEUTRAL_B = 128;
-const ENEMY_R = 255,
-  ENEMY_G = 0,
-  ENEMY_B = 0;
-
 const TEX_W = getPaletteSize(); // 4096 — covers full 12-bit smallID range
 const TEX_H = 2;
 
@@ -44,7 +31,10 @@ export class AffiliationPalette {
   private relationData: Uint8Array | null = null;
   private relationSize = 0;
 
-  constructor(gl: WebGL2RenderingContext) {
+  constructor(
+    gl: WebGL2RenderingContext,
+    private settings: RenderSettings,
+  ) {
     this.gl = gl;
     this.rebuild(); // initialize to spectator-mode defaults (gray borders, red units)
     this.tex = createTexture2D(gl, {
@@ -100,6 +90,22 @@ export class AffiliationPalette {
     const rel = this.relationData;
     const rs = this.relationSize;
 
+    // Affiliation RGB values (0–1) from render-settings, expanded to 0–255.
+    const a = this.settings.affiliation;
+    const to255 = (v: number) => Math.round(v * 255);
+    const SELF_R = to255(a.selfR),
+      SELF_G = to255(a.selfG),
+      SELF_B = to255(a.selfB);
+    const ALLY_R = to255(a.allyR),
+      ALLY_G = to255(a.allyG),
+      ALLY_B = to255(a.allyB);
+    const NEUTRAL_R = to255(a.neutralR),
+      NEUTRAL_G = to255(a.neutralG),
+      NEUTRAL_B = to255(a.neutralB);
+    const ENEMY_R = to255(a.enemyR),
+      ENEMY_G = to255(a.enemyG),
+      ENEMY_B = to255(a.enemyB);
+
     for (let owner = 0; owner < TEX_W; owner++) {
       // Determine relationship
       let relation = RELATION_NEUTRAL;