Add PVP immunity to 5M starting gold modifier games 🔧 (#3180)

## Description:

Adds 30 seconds of PVP immunity to 5M starting gold modifier games.
So you cannot insta-nuke other players.

Because I'm sure people would be confused "I cannot attack!!!!" I added
a HeadsUpMessage which informs about the PVP immunity.
We already have a ImmunityTimer progress bar but I don't think its
enough.

<img width="1270" height="745" alt="image"
src="https://github.com/user-attachments/assets/0ee23dc4-1c7b-4d62-8b3d-8de214f03c2b"
/>

I had a second count in the HeadsUpMessage (seconds until PVP immunity
is over) but it felt too busy. So I removed it. You can tell when PVP
immunity is over by looking at the progress bar.

## 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:

FloPinguin

---------

Co-authored-by: Evan <evanpelle@gmail.com>

resources/lang/en.json

@@ -845,7 +845,8 @@
     "choose_spawn": "Choose a starting location",
     "random_spawn": "Random spawn is enabled. Selecting starting location for you...",
     "singleplayer_game_paused": "Game paused",
-    "multiplayer_game_paused": "Game paused by Lobby Creator"
+    "multiplayer_game_paused": "Game paused by Lobby Creator",
+    "pvp_immunity_active": "PVP immunity active for {seconds}s"
   },
   "territory_patterns": {
     "title": "Skins",

src/client/graphics/layers/HeadsUpMessage.ts

@@ -16,6 +16,9 @@ export class HeadsUpMessage extends LitElement implements Layer {
   @state()
   private isPaused = false;
 
+  @state()
+  private isImmunityActive = false;
+
   @state()
   private toastMessage: string | import("lit").TemplateResult | null = null;
   @state()
@@ -79,7 +82,18 @@ export class HeadsUpMessage extends LitElement implements Layer {
       this.isPaused = pauseUpdate.paused;
     }
 
-    this.isVisible = this.game.inSpawnPhase() || this.isPaused;
+    const showImmunityHudDuration = 10 * 10;
+    const spawnEnd = this.game.config().numSpawnPhaseTurns();
+    const ticksSinceSpawnEnd = this.game.ticks() - spawnEnd;
+
+    this.isImmunityActive =
+      this.game.config().hasExtendedSpawnImmunity() &&
+      !this.game.inSpawnPhase() &&
+      this.game.isSpawnImmunityActive() &&
+      ticksSinceSpawnEnd < showImmunityHudDuration;
+
+    this.isVisible =
+      this.game.inSpawnPhase() || this.isPaused || this.isImmunityActive;
     this.requestUpdate();
   }
 
@@ -91,6 +105,11 @@ export class HeadsUpMessage extends LitElement implements Layer {
         return translateText("heads_up_message.multiplayer_game_paused");
       }
     }
+    if (this.isImmunityActive) {
+      return translateText("heads_up_message.pvp_immunity_active", {
+        seconds: Math.round(this.game.config().spawnImmunityDuration() / 10),
+      });
+    }
     return this.game.config().isRandomSpawn()
       ? translateText("heads_up_message.random_spawn")
       : translateText("heads_up_message.choose_spawn");

src/client/graphics/layers/ImmunityTimer.ts

@@ -41,7 +41,10 @@ export class ImmunityTimer extends LitElement implements Layer {
     const immunityDuration = this.game.config().spawnImmunityDuration();
     const spawnPhaseTurns = this.game.config().numSpawnPhaseTurns();
 
-    if (immunityDuration <= 5 * 10 || this.game.inSpawnPhase()) {
+    if (
+      !this.game.config().hasExtendedSpawnImmunity() ||
+      this.game.inSpawnPhase()
+    ) {
       this.setInactive();
       return;
     }

src/core/configuration/Config.ts

@@ -58,6 +58,7 @@ export interface NukeMagnitude {
 
 export interface Config {
   spawnImmunityDuration(): Tick;
+  hasExtendedSpawnImmunity(): boolean;
   serverConfig(): ServerConfig;
   gameConfig(): GameConfig;
   theme(): Theme;

src/core/configuration/DefaultConfig.ts

@@ -28,6 +28,7 @@ import { PastelThemeDark } from "./PastelThemeDark";
 
 const DEFENSE_DEBUFF_MIDPOINT = 150_000;
 const DEFENSE_DEBUFF_DECAY_RATE = Math.LN2 / 50000;
+const DEFAULT_SPAWN_IMMUNITY_TICKS = 5 * 10;
 
 const JwksSchema = z.object({
   keys: z
@@ -163,7 +164,12 @@ export class DefaultConfig implements Config {
     return 30 * 10; // 30 seconds
   }
   spawnImmunityDuration(): Tick {
-    return this._gameConfig.spawnImmunityDuration ?? 5 * 10; // default to 5 seconds
+    return (
+      this._gameConfig.spawnImmunityDuration ?? DEFAULT_SPAWN_IMMUNITY_TICKS
+    );
+  }
+  hasExtendedSpawnImmunity(): boolean {
+    return this.spawnImmunityDuration() > DEFAULT_SPAWN_IMMUNITY_TICKS;
   }
 
   gameConfig(): GameConfig {

src/core/game/GameImpl.ts

@@ -722,7 +722,7 @@ export class GameImpl implements Game {
   public isSpawnImmunityActive(): boolean {
     return (
       this.config().numSpawnPhaseTurns() +
-        this.config().spawnImmunityDuration() >=
+        this.config().spawnImmunityDuration() >
       this.ticks()
     );
   }

src/core/game/GameView.ts

@@ -813,6 +813,12 @@ export class GameView implements GameMap {
   inSpawnPhase(): boolean {
     return this.ticks() <= this._config.numSpawnPhaseTurns();
   }
+  isSpawnImmunityActive(): boolean {
+    return (
+      this._config.numSpawnPhaseTurns() + this._config.spawnImmunityDuration() >
+      this.ticks()
+    );
+  }
   config(): Config {
     return this._config;
   }

src/server/MapPlaylist.ts

@@ -160,7 +160,7 @@ export class MapPlaylist {
       gameMode: mode,
       playerTeams,
       bots: isCompact ? 100 : 400,
-      spawnImmunityDuration: 5 * 10,
+      spawnImmunityDuration: startingGold ? 30 * 10 : 5 * 10,
       disabledUnits: [],
     } satisfies GameConfig;
   }

tests/Attack.test.ts

@@ -391,17 +391,17 @@ describe("Attack immunity", () => {
 
   test("Ensure a player can't attack during all the immunity phase", async () => {
     // Execute a few ticks but stop right before the immunity phase is over
-    for (let i = 0; i < immunityPhaseTicks - 1; i++) {
+    for (let i = 0; i < immunityPhaseTicks - 2; i++) {
       game.executeNextTick();
     }
     // Player A attacks Player B
     game.addExecution(new AttackExecution(null, playerA, playerB.id(), null));
-    game.executeNextTick(); // ticks === immunityPhaseTicks here
+    game.executeNextTick(); // ticks === immunityPhaseTicks - 1 here
     // Attack is not possible during immunity
     expect(playerA.outgoingAttacks()).toHaveLength(0);
 
     // Retry after the immunity is over
-    game.executeNextTick(); // ticks === immunityPhaseTicks + 1
+    game.executeNextTick(); // ticks === immunityPhaseTicks
     game.addExecution(new AttackExecution(null, playerA, playerB.id(), null));
     game.executeNextTick();
     // Attack is now possible right after