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/trade.js

@@ -91,7 +91,7 @@ export function addReceptionAnimalToSale(state, receptionCellKey) {
 
 /**
  * Remove expired sale listings. If listing was a baby (isBaby), increment deathCountRecent (bébé invendu meurt).
- * Call from game loop each tick.
+ * If listing was an adult (isBaby false), also increment deathCountRecent (vente échouée = mort adulte).
  * @param {import("./types.js").GameState} state
  * @param {number} nowUnix
  */
@@ -99,24 +99,29 @@ export function tickSaleListings(state, nowUnix) {
   const listings = state.saleListings ?? [];
   const kept = [];
   let babyDeaths = 0;
+  let adultDeaths = 0;
   for (const listing of listings) {
     if (nowUnix < listing.endAt) {
       kept.push(listing);
     } else if (listing.isBaby) {
       babyDeaths += 1;
+    } else {
+      adultDeaths += 1;
     }
   }
   state.saleListings = kept;
-  if (babyDeaths > 0) state.deathCountRecent = (state.deathCountRecent ?? 0) + babyDeaths;
+  const totalDeaths = babyDeaths + adultDeaths;
+  if (totalDeaths > 0) state.deathCountRecent = (state.deathCountRecent ?? 0) + totalDeaths;
 }
 
 /**
+ * Compute sell result for animal at (x,y). Returns [false, reason] or [true, { blockKeys, sellValue }].
  * @param {import("./types.js").GameState} state
  * @param {number} x
  * @param {number} y
- * @returns {[boolean, number | string]}
+ * @returns {[false, string] | [true, { blockKeys: string[], sellValue: number }]}
  */
-export function sellAnimalToNpc(state, x, y) {
+function getSellAnimalResult(state, x, y) {
   const key = cellKey(x, y);
   const cell = state.grid.cells[key];
   if (cell === null || cell === undefined || cell.kind !== "animal") return [false, "NoAnimal"];
@@ -133,6 +138,19 @@ export function sellAnimalToNpc(state, x, y) {
     mutationMultiplier,
     animalDef.sellFactor
   );
+  return [true, { blockKeys, sellValue }];
+}
+
+/**
+ * @param {import("./types.js").GameState} state
+ * @param {number} x
+ * @param {number} y
+ * @returns {[boolean, number | string]}
+ */
+export function sellAnimalToNpc(state, x, y) {
+  const result = getSellAnimalResult(state, x, y);
+  if (result[0] === false) return [false, result[1]];
+  const { blockKeys, sellValue } = result[1];
   for (const k of blockKeys) delete state.grid.cells[k];
   state.coins += sellValue;
   state.lastEvolutionAt = Math.floor(Date.now() / 1000);