Add WPush Notification Provider

[anhao]

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Description

Fixes #(issue)

Type of change

Please delete any options that are not relevant.

• 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)

Screenshots (if any)

test :

down:

up:

[CommanderStorm]

Ok, thanks for the changes 👍
LGTM now

=> merging into v2.0.
See #4500 for further details about said release and what it is missing.