feat: allow users to define custom post types

[sherwinski]

Summary

Allows users to define custom post types via the plugin admin page.

Description

Changes include:

• adding new input to the admin page
• persist field values to onesignal_settings
• toggle save button when custom post types are modified

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This change is 

[sherwinski]

Open Questions

• Reading our docs, will we need to add back this checkbox for Automatically send a push notification when I publish a post from 3rd party plugins? I imagine so based on the old implementation in v2 but figured I check first
• Any recommendations on testing this? Are there any third-party plugins you recommend using or is this something that can be easily mocked?

[rgomezp]

Looking good so far!

We still need to make onesignal_schedule_notification make use of the custom post types settings.

I imagine so based on the old implementation in v2 but figured I check first

Yeah good catch. I think this will be required.

Any recommendations on testing this? Are there any third-party plugins you recommend using or is this something that can be easily mocked?

Unfortunately don't know how our customers use this. Maybe @marclucraft or @jfishman1 have some ideas. Otherwise, I think just researching is the best bet.

[marclucraft]

@sherwinski @rgomezp – I don't have any specific plugins from Customers to suggest, although many use custom post types.

This guide will help to get some setup: https://www.cloudways.com/blog/wordpress-custom-post-type/

[marclucraft]

Since there is work on the settings screen here, we are still seeing reports of Settings not persisting.

A customer has reached out to Support and referenced this WordPress plugin topic
https://wordpress.org/support/topic/cannot-save-option-to-send-to-mobile-app-users/

[skritlaki]

Hello, the situation is much worse than before.
The plugin does not work with the Classic Editor.

I cannot save an article as long as OneSignal is activated.
When OneSignal is active, it triggers an error in the Apache console.

I’m not even mentioning the errors in Chrome/Mozilla's console, which still persist.
Overall, the update made things worse rather than improving them.
Thank you.