[Feature] specify a mount node for tooltip

[ylc395]

Initial checklist

• I agree to follow the code of conduct
• I searched issues and discussions and couldn’t find anything (or linked relevant results below)

Problem

milkdown/packages/plugins/plugin-tooltip/src/tooltip-provider.ts

Line 91 in c7218bf

view.dom.parentElement?.appendChild(this.element)

Tooltip and its derived components like Link Tooltip, is always mounted in milkdown container. This is not suitable when milkdown container or its ancestors has style like overflow: hidden:

Solution

We can provide an extra option like mount to specify a mount node, so users can mount tooltip element into a specified element ( for example, document.body).

If this proposal is acceptable, I can submit a PR.

Alternatives

No