Deleting a subdomain setting also deletes a domain setting ("Personalized Results" settings)

On "Personalized Results" settings page, when subdomains (*.example.com) and domain (example.com) are set separately, deleting the subdomain setting also deletes the domain setting.

Steps to reproduce:

1. Open "Personalized Results" settings. https://kagi.com/settings?p=user_ranked
2. Add subdomains and domains separately (rankings can be the same or different).

   example.com
   mail.example.com
   calendar.example.com

3. Delete the setting for mail.example.com .
4. The setting for example.com is also deleted (while the setting for calendar.example.com remains).

Expected behavior:
Even if they include the same domain, each setting should be processed separately. I found this issue when I tried to organize settings for multiple subdomains.

Debug info:
Arc browser, macOS Monterey, ASIA-EAST

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