Add Diff of Staged Files as a new context

Now that Cursor is adding new contexts to Chat and Composer with new releases, I am reposting this issue that I originally created on GitHub to bring it back into discussion. Cursor uses the forum for bug reports and feature requests, so I wanted to resurface this topic here.

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

I am currently utilizing the @Commit(Diff of Working State) and @PR(Diff with Main Branch) commands to generate commit messages. These features work well, but there is room for improvement.

Describe the solution you’d like

I propose adding an option to view the diff of the Git staging area (e.g., git diff --staged). This addition would allow the AI assistant to generate more accurate and contextual commit messages based on the changes that are staged for committing. It would also enable users to point the assistant to specific staged changes more easily. The command could be named something like @Staged(Diff of Staged Files)

Additional context

These current options are helpful for quickly viewing differences between the current file and the main branch or the working state. However, incorporating an option to view the diff of the staging area would enhance functionality, particularly when generating commit messages or focusing on specific staged changes.