fix: replace unsupported Hrkt unicode property to Hira and Kana

[Bo26fhmC5M]

PR Checklist

• Have you checked if it works normally in all models? Ignore this if it doesn't use models.
• Have you checked if it works normally in all web, local, and node hosted versions? If it doesn't, have you blocked it in those versions?
• Have you added type definitions?

Description

Auto Regenerate On Characterset feature can throw the following error when Hrkt is enabled:

Error while parsing chat message: true, Invalid regular expression: /\p{Script=Hrkt}/gu: Invalid property name

This PR fixes regex parsing issues with unicode property:

1. Replaces unsupported Hrkt property with separate Hira and Kana properties
2. Updates preview text for each property to match the changes