[BUG?] Use `ctrl+A` to select all need press twice

[Zeng1998]

• Searched existing issues to avoid creating duplicates.

• Confirmed that it can be reproduced in muya.

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Describe the bug
need press ctrl+A twice to select all contents.

To Reproduce

1. git clone the latest commit of the repo (version 0.2.5)
2. run pnpm dev
3. visit http://localhost:5173
4. press ctrl+A, but fail to select all.
5. press ctrl+A again, success.

Expected behavior
press ctrl+A once to select all content.

Actual behavior
need press twice to do that.

BTW, is it possible to controll to copy the rich text or the plain markdown text of the selection.

Operation System and Browser version (please complete the following information):

• OS: Windows 11
• Browser: Chrome 121.0.6167.86 (Official Build) (64-bit)

Muya Version
e.g: 0.2.5

Screenshots / Screencasts（Optional）