[ACF Blocks] Feature Request - Hook for header

What's missing: Hooks available for me to add a tag to the header whenever a particular block renders.

Why? : Googles new Page Speed tools measure LCP. (Largest Contentful Paint) LCP, if it's an image, can be drastically reduced by preloading the asset so it loads faster. Therefore I want to make it so that whenever someone uses a hero banner block, it will preload the background image that they set in an ACF image field.

I can't find a way to do this currently even after having a look at available hooks, and appreciate it's not high priority but it would be nice.

Alternatively I can see it would be possible using parse_blocks() possibly and checking the block type of the first few blocks, but seems a lot longer than having a hook available with block ID / fields accessible.

Start by reviewing the available ACF Blocks hooks and the parse_blocks() approach mentioned in the issue. Determine how a block's ID and fields could be exposed when a block renders so a caller can add a preload link for its image. Done means the requested hook behavior and accessible data are defined and documented for this use case.