[feature request] Show attribution for uncommitted AI edits in VS Code?

Hey, thanks for working on git-ai.

I tried the VS Code extension — committed AI attribution shows up nicely, but newly accepted AI edits don't have any attribution in the editor until they're committed. In an IDE, the pre-commit moment is exactly when I most want to see the original prompt that generated this code.

Suggested behavior:

• Committed lines → stable attribution from refs/notes/ai (already works)
• Uncommitted lines with checkpoint data → temporary attribution, e.g. Claude Code · uncommitted
• New lines without checkpoint data → unknown/untracked, not guessed

Important: I'm not asking git-ai to detect AI-written code heuristically. This would only surface attribution that git-ai already has in .git/ai/working_logs/ from checkpoints, including the associated prompt.

Maybe this could be exposed through a stable CLI surface, for example by letting git ai blame optionally include working-tree attribution when given the current file contents. That would let the VS Code extension and third-party editor integrations consume it consistently.