【建议】增加全屏，对标yuque lake editor

[JaneYork]

Description
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Recording
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Sandbox
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Steps
To reproduce the behavior:

1. Go to '...'
2. Click on '....'
3. Scroll down to '....'
4. See error

Expectation
A clear and concise description of what you expected to happen. (Often it's helpful to test out the behavior of other editors like Google Docs, Medium, Notion, etc. to see how they handle the same issue.)

Environment

• Editable Version: [e.g. 0.59]
• Operating System: [e.g. iOS]
• Browser: [e.g. Chrome, Safari]
• TypeScript Version: [e.g. 3.9.7 - required only if it's a TypeScript issue]

Context
Add any other context about the problem here. (The fastest way to have an issue fixed is to create a pull request with working, tested code and we'll help merge it. Editable is solving a pretty complex problem, and we can't do it without active contributors, so thank you so much for your help!)

[big-camel]

全屏其实可以自己实现，使用js把根节点全屏就好了