[Bug] Line Breaks Disappear When Pasting Multiple Cells into Univer Sheet

[chaneasy]

Before you submit this issue, have you checked the following

• Is this really a problem?
• I have searched the Github Issues for similar issues, but did not find anything.

Affected packages and versions

0.5.3

Reproduction link

I discovered a bug when copying multiple cell contents from external sources into Univer Sheet. After pasting, the line breaks within the cell contents disappear, leading to formatting issues.

1. Copy multiple cells from an external application (e.g., tapd, Google Sheets).
2. Paste the copied content into a cell in Univer Sheet.
3. Observe that the line breaks within the pasted content are missing.

Expected behavior

When copying multiple cell contents from external sources and pasting them into Univer, the formatting needs to be preserved.

Actual behavior

The line break formatting is lost when copying multiple cell contents from external sources and pasting them into Univer.

System information

System:
OS: macOS 15.2
CPU: (10) arm64 Apple M1 Pro
Memory: 92.63 MB / 16.00 GB
Shell: 5.9 - /bin/zsh
Binaries:
Node: 21.7.2 - ~/.nvm/versions/node/v21.7.2/bin/node
Yarn: 1.22.22 - /usr/local/bin/yarn
npm: 10.5.0 - ~/.nvm/versions/node/v21.7.2/bin/npm
pnpm: 8.15.5 - /usr/local/bin/pnpm
Browsers:
Chrome: 131.0.6778.205
Safari: 18.2