chore: upgrade TypeScript 4.9 to 5.9, ESLint 8.29 to 8.57, @typescript-eslint 5 to 7

Resolves all TS2345/TS2347/TS7006 type errors introduced by stricter TypeScript 5.x.
Fix Icons.Settings to Icons.Setting, cast account data returns, fix implicit any.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

src/app/plugins/recent-emoji.ts

@@ -42,7 +42,7 @@ export function addRecentEmoji(mx: MatrixClient, unicode: string) {
     entry[1] += 1;
   }
   recentEmoji.unshift(entry);
-  mx.setAccountData(AccountDataEvent.ElementRecentEmoji, {
+  (mx as any).setAccountData(AccountDataEvent.ElementRecentEmoji, {
     recent_emoji: recentEmoji.slice(0, 100),
   });
 }