UI refinements (#2859)

## Description:

UI Refinements requested by @evanpelle  check https://ui.openfront.dev

## 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:

w.o.n

src/client/components/baseComponents/stats/DiscordUserHeader.ts

@@ -1,7 +1,7 @@
 import { LitElement, html } from "lit";
 import { customElement, property, state } from "lit/decorators.js";
 import type { DiscordUser } from "../../../../core/ApiSchemas";
-import { translateText } from "../../../Utils";
+import { getDiscordAvatarUrl, translateText } from "../../../Utils";
 
 @customElement("discord-user-header")
 export class DiscordUserHeader extends LitElement {
@@ -23,15 +23,7 @@ export class DiscordUserHeader extends LitElement {
   private get avatarUrl(): string | null {
     const u = this._data;
     if (!u) return null;
-    if (u.avatar) {
-      const ext = u.avatar.startsWith("a_") ? "gif" : "png";
-      return `https://cdn.discordapp.com/avatars/${u.id}/${u.avatar}.${ext}`;
-    }
-    if (u.discriminator !== undefined) {
-      const idx = Number(u.discriminator) % 5;
-      return `https://cdn.discordapp.com/embed/avatars/${idx}.png`;
-    }
-    return null;
+    return getDiscordAvatarUrl(u);
   }
 
   private get discordDisplayName(): string {