Update README.md with MVP Requirements

[jonnywatersbb]

For discussion before committing to docs/README.md

MVP Requirements

Minimum feature list required in order for this project to be considered stable.

• Should be tested on WordPress 5.8 and above and PHP 8+
• Load the active theme.json file from the current theme and render a UI to represent this to the user.
• Display live code preview of the theme.json file to instantly see how a setting change in the UI is altered in theme.json
• Dynamic support for all fields in theme.json
• Ability to edit the value of any theme.json field via the UI and save the changes
• Changes should be stored to the database in a manner compatible with WP Core, including the core styles UI
• Export/download an updated theme.json file
• Reset your overall changes and revert back to the original theme.json file
• Validation on all input fields
• Validation to prevent invalid changes to theme.json file
• Inform the user when a corrupt/invalid theme.json is loaded
• Fully compatible with multisite
• Match WP Core look and feel

[jonnywatersbb]

@scottblackburn @g-elwell

Just adding this as an issue initially for transparency in agreeing the MVP requirements.

Questions on this initially:

1. Inform the user when a corrupt/invalid theme.json is loaded - Is this remaining part of MVP?
2. Are any of the below features already part of the plugin, or should be considered for MVP:

• Restrict overall permissions by user role, configurable by admins via a settings page
• Should include relevant hooks and filters for customisation
• Reset/revert per field
• Support custom properties added to blocks in block.json file

3. Anything else not mentioned there that should be part of MVP

[g-elwell]

@scottblackburn @g-elwell

Just adding this as an issue initially for transparency in agreeing the MVP requirements.

Questions on this initially:

1. Inform the user when a corrupt/invalid theme.json is loaded - Is this remaining part of MVP?

I think this should remain MVP as it's pretty vital to prevent the plugin crashing.

2. Are any of the below features already part of the plugin, or should be considered for MVP:

• Restrict overall permissions by user role, configurable by admins via a settings page
• Should include relevant hooks and filters for customisation
• Reset/revert per field
• Support custom properties added to blocks in block.json file

None of this is already present and they all feel like they'd expand the scope to the point of delaying a v1 release, so suggest we leave them for later

3. Anything else not mentioned there that should be part of MVP

Nothing is coming to mind!

[PaulREnglish]

Is the list of MVP requirements in the OP ready to be committed to README or does it need more discussion @jonnywatersbb @g-elwell ?

[g-elwell]

I'm happy that the MVP requirements are correct but I'm unsure if we should commit that list directly or re-write to be more "user-centric". What do you think @jonnywatersbb

[jonnywatersbb]

Yeah, leave it with me. We'll do this closer to release

[g-elwell]

Resolved by #110