refactor: collapse per-env Configs into ClientEnv + ServerEnv (#3906)

## Description:

This is a refactor to simplify config handling.

Replaces the per-environment DevConfig/PreprodConfig/ProdConfig class
hierarchy with two static classes: ClientEnv (browser main thread, reads
from window.BOOTSTRAP_CONFIG) and ServerEnv (Node server, reads from
process.env). The four config classes are deleted, the abstract
DefaultServerConfig is gone, and DefaultConfig is renamed to Config.

The values that flow server → client (gameEnv, numWorkers,
turnstileSiteKey, jwtAudience, instanceId) used to be baked into the
hardcoded per-env classes. They're now real env vars on the server,
embedded into a single window.BOOTSTRAP_CONFIG object in index.html at
request time (alongside the existing gitCommit/assetManifest/cdnBase
globals, which moved into the same object), and read back by ClientEnv
on the client. The dev defaults previously hidden inside DevServerConfig
are now explicit in start:server-dev (NUM_WORKERS=2,
TURNSTILE_SITE_KEY=1x..., JWT_AUDIENCE=localhost, etc.) and in
vite.config.ts's html plugin inject.data. Production deploys plumb
NUM_WORKERS and TURNSTILE_SITE_KEY through deploy.yml (GitHub vars) into
the remote env file; JWT_AUDIENCE is derived from DOMAIN in deploy.sh.
The dynamic /api/instance endpoint is gone — INSTANCE_ID rides along in
BOOTSTRAP_CONFIG now.

ServerEnv is the only thing server code touches; ClientEnv is
browser-only. The two classes have intentional overlap (env, numWorkers,
jwtIssuer, gameCreationRate, workerIndex, etc.) since they derive
identical logic from different sources — there's a TODO in each to
consolidate via a shared helper later. The game-logic Config no longer
stores a ServerConfig/ClientEnv reference and its serverConfig() getter
is gone; the one caller (MultiTabModal) now reads ClientEnv.env()
directly. Worker init no longer carries server-config values since
nothing in the worker actually reads them.

## 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
- [x] I confirm I have thoroughly tested these changes and take full
responsibility for any bugs introduced

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

evan

tests/server/Archive.test.ts

@@ -1,13 +1,13 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
-vi.mock("../../src/core/configuration/ConfigLoader", () => ({
-  getServerConfigFromServer: () => ({
+vi.mock("../../src/server/ServerEnv", () => ({
+  ServerEnv: {
     jwtIssuer: () => "https://archive.test.invalid",
     apiKey: () => "test-key",
     gitCommit: () => "DEV",
     subdomain: () => "test",
     domain: () => "test",
-  }),
+  },
 }));
 
 vi.mock("../../src/server/Logger", () => ({

tests/server/GameLifecycle.test.ts

@@ -1,17 +1,5 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
-vi.mock("../../src/core/configuration/ConfigLoader", () => ({
-  getServerConfigFromServer: () => ({
-    otelEnabled: () => false,
-    otelAuthHeader: () => "",
-    otelEndpoint: () => "",
-    env: () => 0, // GameEnv.Dev
-  }),
-  getServerConfig: () => ({
-    otelEnabled: () => false,
-  }),
-}));
-
 vi.mock("../../src/core/Schemas", async () => {
   const actual = (await vi.importActual("../../src/core/Schemas")) as any;
   return {
@@ -25,13 +13,11 @@ vi.mock("../../src/core/Schemas", async () => {
   };
 });
 
-import { GameEnv } from "../../src/core/configuration/Config";
 import { GameType } from "../../src/core/game/Game";
 import { GameServer } from "../../src/server/GameServer";
 
 describe("GameLifecycle", () => {
   let mockLogger: any;
-  let mockConfig: any;
 
   beforeEach(() => {
     vi.useFakeTimers();
@@ -41,11 +27,6 @@ describe("GameLifecycle", () => {
       warn: vi.fn(),
       error: vi.fn(),
     };
-    mockConfig = {
-      turnIntervalMs: () => 100,
-      gameCreationRate: () => 1000,
-      env: () => GameEnv.Dev,
-    };
   });
 
   afterEach(() => {
@@ -54,13 +35,9 @@ describe("GameLifecycle", () => {
   });
 
   it("should not start turn interval if game has ended", async () => {
-    const game = new GameServer(
-      "test-game",
-      mockLogger,
-      Date.now(),
-      mockConfig,
-      { gameType: GameType.Private } as any,
-    );
+    const game = new GameServer("test-game", mockLogger, Date.now(), {
+      gameType: GameType.Private,
+    } as any);
 
     // Call end() first - this should set _hasEnded
     await game.end();
@@ -77,17 +54,11 @@ describe("GameLifecycle", () => {
 
   it("should clear turn interval and set _hasEnded on end()", async () => {
     // We need to initialize the game such that start() can succeed
-    const game = new GameServer(
-      "test-game",
-      mockLogger,
-      Date.now(),
-      mockConfig,
-      {
-        gameType: GameType.Private,
-        gameMap: "plains",
-        gameMapSize: 100,
-      } as any,
-    );
+    const game = new GameServer("test-game", mockLogger, Date.now(), {
+      gameType: GameType.Private,
+      gameMap: "plains",
+      gameMapSize: 100,
+    } as any);
 
     // Manually trigger prestart to fulfill some internal checks if necessary
     game.prestart();
@@ -103,13 +74,9 @@ describe("GameLifecycle", () => {
   });
 
   it("should be resilient to multiple end() calls", async () => {
-    const game = new GameServer(
-      "test-game",
-      mockLogger,
-      Date.now(),
-      mockConfig,
-      { gameType: GameType.Private } as any,
-    );
+    const game = new GameServer("test-game", mockLogger, Date.now(), {
+      gameType: GameType.Private,
+    } as any);
 
     await game.end();
     expect((game as any)._hasEnded).toBe(true);

tests/server/KickPlayerAuthorization.test.ts

@@ -1,17 +1,5 @@
 import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 
-vi.mock("../../src/core/configuration/ConfigLoader", () => ({
-  getServerConfigFromServer: () => ({
-    otelEnabled: () => false,
-    otelAuthHeader: () => "",
-    otelEndpoint: () => "",
-    env: () => 0, // GameEnv.Dev
-  }),
-  getServerConfig: () => ({
-    otelEnabled: () => false,
-  }),
-}));
-
 vi.mock("../../src/core/Schemas", async () => {
   const actual = (await vi.importActual("../../src/core/Schemas")) as any;
   return {
@@ -69,7 +57,6 @@ function makeClient(
 
 describe("GameServer - kick_player authorization", () => {
   let mockLogger: any;
-  let mockConfig: any;
 
   beforeEach(() => {
     vi.useFakeTimers();
@@ -79,11 +66,6 @@ describe("GameServer - kick_player authorization", () => {
       warn: vi.fn(),
       error: vi.fn(),
     };
-    mockConfig = {
-      turnIntervalMs: () => 100,
-      gameCreationRate: () => 1000,
-      env: () => 0,
-    };
   });
 
   afterEach(() => {
@@ -96,7 +78,6 @@ describe("GameServer - kick_player authorization", () => {
       "test-game",
       mockLogger,
       Date.now(),
-      mockConfig,
       { gameType: GameType.Private } as any,
       creatorPersistentID,
     );

tests/server/MasterLobbyServiceHealth.test.ts

@@ -1,7 +1,7 @@
 import EventEmitter from "events";
 import { describe, expect, it, vi } from "vitest";
 import { MasterLobbyService } from "../../src/server/MasterLobbyService";
-import { TestServerConfig } from "../util/TestServerConfig";
+import { ServerEnv } from "../../src/server/ServerEnv";
 
 vi.mock("../../src/server/Logger", () => ({
   logger: {
@@ -27,10 +27,9 @@ function sendWorkerReady(worker: EventEmitter, workerId: number) {
 }
 
 function createService(numWorkers: number): MasterLobbyService {
-  const config = new TestServerConfig();
-  vi.spyOn(config, "numWorkers").mockReturnValue(numWorkers);
+  vi.spyOn(ServerEnv, "numWorkers").mockReturnValue(numWorkers);
   const log = { info: vi.fn(), error: vi.fn() } as any;
-  return new MasterLobbyService(config, {} as any, log);
+  return new MasterLobbyService({} as any, log);
 }
 
 function startAllWorkers(

tests/server/RenderHtml.test.ts

@@ -1,7 +1,7 @@
 import fs from "fs/promises";
 import os from "os";
 import path from "path";
-import { afterEach, describe, expect, test } from "vitest";
+import { afterEach, beforeEach, describe, expect, test, vi } from "vitest";
 import {
   clearAppShellContentCache,
   getAppShellContent,
@@ -12,7 +12,14 @@ describe("RenderHtml", () => {
   const originalGitCommit = process.env.GIT_COMMIT;
   let tempDir: string | null = null;
 
+  beforeEach(() => {
+    vi.stubEnv("NUM_WORKERS", "1");
+    vi.stubEnv("TURNSTILE_SITE_KEY", "test-key");
+    vi.stubEnv("DOMAIN", "localhost");
+  });
+
   afterEach(async () => {
+    vi.unstubAllEnvs();
     process.env.GIT_COMMIT = originalGitCommit;
     clearAppShellContentCache();
 

tests/server/ServerEnv.test.ts

@@ -0,0 +1,109 @@
+import { afterEach, describe, expect, test, vi } from "vitest";
+import { ServerEnv } from "../../src/server/ServerEnv";
+
+describe("ServerEnv.numWorkers", () => {
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
+
+  test("returns parsed value when valid", () => {
+    vi.stubEnv("NUM_WORKERS", "4");
+    expect(ServerEnv.numWorkers()).toBe(4);
+  });
+
+  test("throws when unset", () => {
+    vi.stubEnv("NUM_WORKERS", "");
+    expect(() => ServerEnv.numWorkers()).toThrow(/NUM_WORKERS not set/);
+  });
+
+  test("throws on non-numeric", () => {
+    vi.stubEnv("NUM_WORKERS", "abc");
+    expect(() => ServerEnv.numWorkers()).toThrow(/Invalid NUM_WORKERS/);
+  });
+
+  test("throws on zero", () => {
+    vi.stubEnv("NUM_WORKERS", "0");
+    expect(() => ServerEnv.numWorkers()).toThrow(/Invalid NUM_WORKERS/);
+  });
+
+  test("throws on negative", () => {
+    vi.stubEnv("NUM_WORKERS", "-2");
+    expect(() => ServerEnv.numWorkers()).toThrow(/Invalid NUM_WORKERS/);
+  });
+});
+
+describe("ServerEnv.turnstileSiteKey", () => {
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
+
+  test("returns value when set", () => {
+    vi.stubEnv("TURNSTILE_SITE_KEY", "site-key");
+    expect(ServerEnv.turnstileSiteKey()).toBe("site-key");
+  });
+
+  test("throws when unset", () => {
+    vi.stubEnv("TURNSTILE_SITE_KEY", "");
+    expect(() => ServerEnv.turnstileSiteKey()).toThrow(
+      /TURNSTILE_SITE_KEY not set/,
+    );
+  });
+});
+
+describe("ServerEnv.jwtAudience", () => {
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
+
+  test("returns DOMAIN when set", () => {
+    vi.stubEnv("DOMAIN", "openfront.io");
+    expect(ServerEnv.jwtAudience()).toBe("openfront.io");
+  });
+
+  test("throws when DOMAIN unset", () => {
+    vi.stubEnv("DOMAIN", "");
+    expect(() => ServerEnv.jwtAudience()).toThrow(/DOMAIN not set/);
+  });
+});
+
+describe("ServerEnv.jwtIssuer", () => {
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
+
+  test("maps 'localhost' to http://localhost:8787", () => {
+    vi.stubEnv("DOMAIN", "localhost");
+    expect(ServerEnv.jwtIssuer()).toBe("http://localhost:8787");
+  });
+
+  test("derives api.<audience> for non-localhost", () => {
+    vi.stubEnv("DOMAIN", "openfront.io");
+    expect(ServerEnv.jwtIssuer()).toBe("https://api.openfront.io");
+  });
+});
+
+describe("ServerEnv.allowedFlares", () => {
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
+
+  test("returns undefined when unset", () => {
+    vi.stubEnv("ALLOWED_FLARES", "");
+    expect(ServerEnv.allowedFlares()).toBeUndefined();
+  });
+
+  test("parses a single value", () => {
+    vi.stubEnv("ALLOWED_FLARES", "admin");
+    expect(ServerEnv.allowedFlares()).toEqual(["admin"]);
+  });
+
+  test("parses CSV", () => {
+    vi.stubEnv("ALLOWED_FLARES", "admin,beta,internal");
+    expect(ServerEnv.allowedFlares()).toEqual(["admin", "beta", "internal"]);
+  });
+
+  test("trims whitespace and drops empties", () => {
+    vi.stubEnv("ALLOWED_FLARES", " admin , , beta ");
+    expect(ServerEnv.allowedFlares()).toEqual(["admin", "beta"]);
+  });
+});