Add OneChat notification provider

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Description

This PR adds a new Notification Provider for OneChat, allowing users to receive alerts and notifications directly via OneChat.
Fixes #(issue)

Type of change

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• New feature (non-breaking change which adds functionality)

Checklist

• My code follows the style guidelines of this project
• I ran ESLint and other linters for modified files
• I have performed a self-review of my own code and tested it
• I have commented my code, particularly in hard-to-understand areas (including JSDoc for methods)
• My changes generates no new warnings
• My code needed automated testing. I have added them (this is optional task)

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[CommanderStorm]

Overall looks good. There are a few changes I'd like to see before we can merge this in v2.1