fix: move mail from shared group inbox to personal inbox #375

hooks/use-mailbox-drop.ts

@@ -173,7 +173,11 @@ export function useMailboxDrop({ mailbox, onDropComplete, onSuccess, onError }:
         // import call to target the owner's JMAP account.
         const jmapDestId = mailbox.originalId || mailbox.id;
         const destJmapOverride = mailbox.isShared ? mailbox.accountId : undefined;
-        await crossAccountMoveEmails(bySource, destAccountId, jmapDestId, destJmapOverride);
+        // Mirror image for the source: a shared group mailbox is accessed
+        // through the viewing user's client, but the email/blob live in the
+        // owner's JMAP account, so the copy/delete must target it.
+        const sourceJmapOverride = sourceMb?.isShared ? sourceMb.accountId : undefined;
+        await crossAccountMoveEmails(bySource, destAccountId, jmapDestId, destJmapOverride, sourceJmapOverride);
       } else {
         // Single-account or same-account-shared move: bulk JMAP request.
         await moveEmailsToMailbox(client, emailIds, mailbox.id);