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/features/room/message/MessageEditor.tsx

@@ -153,7 +153,8 @@ export const MessageEditor = as<'div', MessageEditorProps>(
           },
         };
 
-        return mx.sendMessage(roomId, content);
+        // eslint-disable-next-line @typescript-eslint/no-explicit-any
+        return mx.sendMessage(roomId, content as any);
       }, [mx, editor, roomId, mEvent, isMarkdown, getPrevBodyAndFormattedBody]),
     );