fix: resolve sync count inflation, add essence/s display, sort auto-buy by level

Closes #147: patch functions now detect actual changes before incrementing
the patched counter, preventing inflated sync reports.

Closes #149: computeEssencePerSecond exported from tick engine and shown
in the resource bar dropdown alongside Gold/s.

Closes #150: auto-buy now sorts adventurers by level descending for
semantic clarity, ensuring highest-tier units are purchased first.

apps/web/src/context/gameContext.tsx

@@ -1127,7 +1127,7 @@ export const GameProvider = ({
               return adventurer.unlocked && next.resources.gold >= cost;
             }).
             sort((adventurerA, adventurerB) => {
-              return adventurerB.combatPower - adventurerA.combatPower;
+              return adventurerB.level - adventurerA.level;
             });
           if (bestAdventurer !== undefined) {
             const purchaseCost