The tree takes root

Added

• Branch tree view with parent tracking, shipped work placed under its release.
• Branch commit list with per-commit diffs, plus revert, cherry-pick and reset.
• Merge into any local branch, with merge options; branch reset; git file watcher.
• Delete remote branches and clean up merged children.
• Stash action and uncommitted file count per branch.
• Resizable panes and collapsible branches panel.