add notes on max message size

Signed-off-by: xsbfh <z6MkpzZDoFM7tPZPXqvaVCtMFxKJQAxghVRJZxsf8s8SqBvm@dev.smashchats.com>

Author: xsbfh

src/shared/constants/protocol.ts

@@ -1,3 +1,6 @@
 export const EXPIRATION_TIME_MS = 7 * 24 * 60 * 60 * 1000; // 7 days
 export const SESSION_TTL_MS = EXPIRATION_TIME_MS;
-export const MAX_MESSAGE_SIZE = 512 * 1024; // 512KB
+// MAX_MESSAGE_SIZE set to 512KB to match socket.io cap
+// https://socket.io/fr/how-to/upload-a-file
+// Note that files shouldnt be sent as Smash messages, but with CDN protocols
+export const MAX_MESSAGE_SIZE = 512 * 1024;