FEAT: ADD CUSTOM BLOCKS (i.e iframe) and customise it like image i.e on double click it open assets options for video link in custom iframe block

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What are you trying to add to GrapesJS?

Describe your feature request detailed

Is there an alternative at the latest version?

• Yes (describe the alternative)
• No

Is this related to an issue?

• Yes (Give a link to the issue)
• No