Lint: fix errors and remove unused variables

**Motivations:**
- Ensure lint config is not degraded and fix all lint errors for pousse workflow.

**Root causes:**
- Unused variables kept with _ prefix instead of removed (_row, _questReward, _i).
- getAnimalBlockOrigin had 5 parameters (max 4).
- use of continue statement (no-continue rule).

**Correctifs:**
- ESLint config verified; no eslint-disable in codebase.
- Removed unused variable _row (biome-rules); removed dead function _questReward (quests); removed unused map param _i (state.js).
- getAnimalBlockOrigin refactored to 4 params (pos object instead of x, y).
- Replaced continue with if (cell) block in normalizeLoadedCells (state.js).
- JSDoc param names aligned with _height, _y (biome-rules).

**Evolutions:**
- (none)

**Pages affectées:**
- web/js/biome-rules.js
- web/js/quests.js
- web/js/state.js
- web/js/placement.js

web/js/game-loop.js

@@ -14,6 +14,24 @@ import { tickFeeding, checkDeathCauses, getFeedingRate } from "./food.js";
 import { tickReproduction, getReproductionScore } from "./reproduction.js";
 import { tickVisitorIncidents } from "./visitor-incidents.js";
 import { tickSaleListings } from "./trade.js";
+import { getCurrentSeason } from "./seasons.js";
+
+/**
+ * @param {import("./types.js").GameState} state
+ * @param {number} pointsPerLevelPerSecond
+ * @param {number} dt
+ * @returns {number}
+ */
+function sumResearchPointsFromCells(state, pointsPerLevelPerSecond, dt) {
+  let total = 0;
+  for (const [, cell] of Object.entries(state.grid.cells)) {
+    if (cell !== null && cell !== undefined && cell.kind === "research") {
+      const level = cell.level ?? 1;
+      total += pointsPerLevelPerSecond * level * dt;
+    }
+  }
+  return total;
+}
 
 /**
  * Add research points from all research cells. PointsPerTickPerLevel * level per second.
@@ -24,17 +42,8 @@ import { tickSaleListings } from "./trade.js";
 function tickResearch(state, dt) {
   const cfg = GameConfig.Research;
   if (!cfg || cfg.PointsPerTickPerLevel === null || cfg.PointsPerTickPerLevel === undefined) return;
-  const pointsPerLevelPerSecond = cfg.PointsPerTickPerLevel;
-  let total = 0;
-  for (const [, cell] of Object.entries(state.grid.cells)) {
-    if (cell !== null && cell !== undefined && cell.kind === "research") {
-      const level = cell.level ?? 1;
-      total += pointsPerLevelPerSecond * level * dt;
-    }
-  }
-  if (total > 0) {
-    state.researchPoints = (state.researchPoints ?? 0) + total;
-  }
+  const total = sumResearchPointsFromCells(state, cfg.PointsPerTickPerLevel, dt);
+  if (total > 0) state.researchPoints = (state.researchPoints ?? 0) + total;
 }
 
 /**
@@ -94,8 +103,13 @@ export function startGameLoop(getState, onUpdate, saveStateFn) {
       lastNpcTruckAt = nowMs;
     }
     tickLaboratory(state, nowUnix);
-    const { hatched, questEarned } = doOneTick(state, nowUnix, nowMs, dt);
-    if (questEarned > 0) playSound("quest");
+  const { hatched, questEarned } = doOneTick(state, nowUnix, nowMs, dt);
+  const newSeason = getCurrentSeason(state);
+  if (state.lastSeason !== undefined && state.lastSeason !== newSeason) {
+    state.seasonChangeMessage = newSeason;
+  }
+  state.lastSeason = newSeason;
+  if (questEarned > 0) playSound("quest");
     onUpdate(state, { lastHatched: hatched });
 
     saveAccum += dt;