feat(compare): add branch and tag comparison features #13
Description
Description
Add comprehensive comparison features for branches, tags, and arbitrary commits.
Requirements
- Compare branches (show commits unique to each)
- Compare tags
- Compare arbitrary commits (picker UI)
- Three-way merge view for conflict resolution
- Visual representation of divergence
Technical Notes
- LibGit2Sharp for commit comparison and merge base
- Integration with VS diff tools for three-way merge
- Consider graph visualization for branch comparison
Related Issues
- feat(diff): add diff integration features #6 - Diff integration features (provides base diff functionality that this extends)
- feat(views): add Branches management tool window #22 - Branches management (provides branch context for comparisons)
- feat(views): add Tags management tool window #23 - Tags management (provides tag context for comparisons)
Note: This issue extends the basic diff capabilities from #6 with advanced comparison views specifically for branches and tags, including visual divergence representation.