Remove unused processName util and twemoji dependency (#1683)

## Description:
This PR removes the unused `processName` utility function from `Util.ts`
and its dependency, the `twemoji` package.

The `processName` function has been commented out and non-operational
for approximately 9 months. This cleanup removes the dead code. As a
result, the `twemoji` npm package is no longer needed and has been
removed from the project's dependencies, which slightly reduces the
overall dependency footprint.

## 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
- [X] I have read and accepted the CLA agreement (only required once).

## Please put your Discord username so you can be contacted if a bug or
regression is found:

aaa4xu

src/core/game/PlayerImpl.ts

@@ -112,7 +112,7 @@ export class PlayerImpl implements Player {
     this._name = sanitizeUsername(playerInfo.name);
     this._troops = toInt(startTroops);
     this._gold = 0n;
-    this._displayName = this._name; // processName(this._name)
+    this._displayName = this._name;
     this._pseudo_random = new PseudoRandom(simpleHash(this.playerInfo.id));
   }