markdown编辑器中部分markdown语法不支持

[bluesky4485]

Pre-submit Checks

• I have searched Zap issues and there are no duplicates.
• This bug is in Zap itself — not in upstream Zap's cloud account, billing, Warpify SSO, or cloud-only features.
• I have included relevant logs (RUST_LOG=info output, panic traces, etc.). Optional, but greatly speeds up triage.
• If the bug is in the AI / BYOP path, I have included the provider name, base URL pattern (redacted), and model id.

Describe the bug

markdown文件编辑的时候，写入类似

*zap很好用*

预览时中文乱码了，好像是斜体字体不支持。

To reproduce

随便找个文件夹新建个md文件，输入zap很好用 预览 即可看到乱码方框效果

Expected behavior

No response

Screenshots, videos, and logs

No response

Operating system (OS)

Windows

Operating system and version

Windows 10 22H2

Shell version

No response

Zap version / commit

v2026.06.04.1

AI / BYOP path involved?

No — non-AI bug (terminal, blocks, UI, shortcuts, etc.)

BYOP provider (if applicable)

No response

Regression

No, this issue has existed throughout my use of Zap.

Last known good build / date (if regression)

No response

Additional context

No response

Does this block your daily use of Zap?

No

Reproducible only in Zap?

Only in Zap.