Add draft saving for commits #6198

Is your feature request related to a problem? Please describe.

I need to commit changes in file1

• I stage file1 and write the commit message
• Commit -> error, pre-commit hook failed due to a problem in file 2.
• I unstage file1 and fix file2, then commit, I still see message from file1 commit. I remove that message an write message for file2 commit.
• Stage again file1 and commit, have to write message all over again because it was not saved

Describe the solution you'd like

I would like a S binding that saves a draft of the message under a given name, so that it can be reused when I come back from file2 to continue with file1.

Describe alternatives you've considered

Deleting the file1 commit message, writing the file2 message and then writing the same file1 commit message again.

Additional context

Add any other context or screenshots about the feature request here.