Add Full Screen Mode Support for Block Editor (JSON Blocks)

Summary Request to add full screen mode support for the block editor when working with JSON blocks, allowing content editors to have a more focused and distraction-free editing experience. Basic Example ![image]( Motivation Content editors frequently need to work with complex JSON block structures that contain significant amounts of content. The current confined editing space makes it difficult to maintain context and focus when working on larger content pieces. Also since this is already supported by the normal editor, it would help keep consistency. Detailed Design Detailed Design The implementation should extend the existing full screen capability to the block editor when working with JSON blocks. This would include: UI Component: Add a full screen toggle button in the block editor toolbar when editing JSON blocks, similar to what exists for other content types. When in full screen mode, the editor should: Expand to cover the entire viewport Hide all other UI …