Docs: Document the missing parameters of render_block_core_block()

[som3669]

render_block_core_block() is the render callback registered for the core/block block and receives three arguments, but its docblock only documented $attributes.

$content and $block_instance were never documented, even though $block_instance is used in the function body to attach the referenced pattern's blocks as inner blocks (parsed_block['innerBlocks']), refresh its context dependents, and render the result.

The new descriptions follow the wording used by the majority of core block render callbacks (Block default content. and Block instance., which are the most common phrasings in src/wp-includes/blocks/), and the @param block is aligned. The blank line between the @param block and @return is also removed, per the Inline Documentation Standards.

Testing

• php -l clean on the changed file.
• Documentation only, no behaviour change — no runtime code is touched.

Trac ticket: https://core.trac.wordpress.org/ticket/65860

Use of AI Tools

AI assistance: Yes
Tool(s): Claude Code
Model(s): Claude Opus 5
Used for: Repository scanning to identify potential documentation/signature inconsistencies, and drafting this change. Reviewed by me.

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