chore: stronger easing method type, add default easing method

Author: Miodec

frontend/src/ts/elements/xp-bar.ts

@@ -404,7 +404,7 @@ async function animateXpBar(
 
     let firstOneDone = false;
     let animationDuration = quickSpeed;
-    let animationEasing = "linear";
+    let animationEasing: Misc.JQueryEasing = "linear";
     let decrement = 1 - (startingLevel % 1);
 
     do {

frontend/src/ts/utils/misc.ts

@@ -449,11 +449,45 @@ export function isAnyPopupVisible(): boolean {
   return popupVisible;
 }
 
+export type JQueryEasing =
+  | "linear"
+  | "swing"
+  | "easeInSine"
+  | "easeOutSine"
+  | "easeInOutSine"
+  | "easeInQuad"
+  | "easeOutQuad"
+  | "easeInOutQuad"
+  | "easeInCubic"
+  | "easeOutCubic"
+  | "easeInOutCubic"
+  | "easeInQuart"
+  | "easeOutQuart"
+  | "easeInOutQuart"
+  | "easeInQuint"
+  | "easeOutQuint"
+  | "easeInOutQuint"
+  | "easeInExpo"
+  | "easeOutExpo"
+  | "easeInOutExpo"
+  | "easeInCirc"
+  | "easeOutCirc"
+  | "easeInOutCirc"
+  | "easeInBack"
+  | "easeOutBack"
+  | "easeInOutBack"
+  | "easeInElastic"
+  | "easeOutElastic"
+  | "easeInOutElastic"
+  | "easeInBounce"
+  | "easeOutBounce"
+  | "easeInOutBounce";
+
 export async function promiseAnimation(
   el: JQuery,
   animation: Record<string, string>,
   duration: number,
-  easing: string
+  easing: JQueryEasing = "swing"
 ): Promise<void> {
   return new Promise((resolve) => {
     el.animate(animation, applyReducedMotion(duration), easing, resolve);