fix: change ReadOnlyAccount type to 'grimoire-readonly' to avoid conflict

The registerCommonAccountTypes() from applesauce-accounts already
registers a ReadOnlyAccount with type 'readonly', causing a duplicate
registration error. Changed our custom ReadOnlyAccount type to
'grimoire-readonly' to avoid the conflict.

src/lib/account-types.ts

@@ -59,7 +59,7 @@ export class ReadOnlyAccount extends BaseAccount<
   void,
   ReadOnlyMetadata
 > {
-  static readonly type = "readonly";
+  static readonly type = "grimoire-readonly";
 
   constructor(pubkey: string, signer: ReadOnlySigner) {
     super(pubkey, signer);