With the introduction of Block Bindings, it became more common to see workflows where users need to see the custom fields that are available or connected. They were relying on the meta key, however it feelt too technical sometimes. The solution is adding a new label argument to include a human-readable name that can be used across the UI.
Props santosguillamot, mamaduka, gziolo, timothyblynjacobs, peterwilsoncc.
Fixes#61998.
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