Remove segment marker assignment in WordPress

[galbus]

This pull request removes all logic related to the beyondwordsMarker attribute from both the PHP backend and JavaScript frontend. The attribute is no longer added to blocks, its controls and UI have been removed, and all related helper functions and code paths have been deleted. Additionally, new logic is introduced to ensure BeyondWords attributes and controls are only added to supported content blocks, preventing issues with internal or UI blocks.

Removal of beyondwordsMarker attribute and related logic:

• Stopped adding the beyondwordsMarker attribute to Gutenberg blocks and removed the associated filter and rendering logic from BlockAttributes.php. The attribute is now deprecated and only kept for backward compatibility in registration. [1] [2] [3]
• Removed all PHP methods for injecting the marker attribute into rendered HTML, including addMarkerAttribute, addMarkerAttributeWithHTMLTagProcessor, and addMarkerAttributeWithDOMDocument from PostContentUtils.php.
• Updated post content rendering to no longer add marker attributes to block HTML output. [1] [2]
• Deleted the unused getSegments method, which previously handled segmenting content by blocks and markers.

Frontend JavaScript cleanup and improvements:

• Removed all marker attribute logic from the block attribute and control registration, including the getBlockMarkerAttribute helper and related filters. [1] [2] [3] [4] [5] [6] [7]
• Introduced the isBeyondwordsSupportedBlock utility to ensure BeyondWords attributes and controls are only added to appropriate content blocks, skipping internal, UI, and container blocks.
• Updated attribute and control registration logic to use this new utility, preventing issues with non-content blocks. [1] [2]

Documentation and comments:

• Updated docblocks and inline comments to reflect the removal of marker logic and clarify the new supported block logic. [1] [2] [3] [4] [5]

These changes streamline the codebase, prevent potential UI issues, and clarify the plugin's behavior regarding block attributes.

[linear]

S-7711 WP plugin removing + block