[FEATURE] Desktop: Add diff filters for uncommitted changes and session changes

Preflight Checklist

• [x] I have searched existing requests and this feature hasn't been requested yet
• [x] This is a single feature request (not multiple features)

Problem Statement

When looking at the diff for a Claude Code session it would be really helpful to see the changes that have happened during the session instead of the full branch diff since a pull requests will sometimes span multiple sessions.

Proposed Solution

Currently the diff viewer allows you to filter to All Changes and to specific commits. It would be helpful to either be able to filter to uncommitted changes or to changes that have been made during this chat session

Alternative Solutions

_No response_

Priority

Medium - Would be very helpful

Feature Category

Other

Use Case Example

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Additional Context

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