feat(diff): render the diff like GitHub, unified and side by side

Cargo.toml

@@ -25,6 +25,7 @@ gpui = { git = "https://github.com/zed-industries/zed" }
 gpui_platform = { git = "https://github.com/zed-industries/zed", features = ["font-kit"] }
 gpui-component = { git = "https://github.com/longbridge/gpui-component", features = ["tree-sitter", "tree-sitter-diff", "tree-sitter-rust"] }
 gpui-component-assets = { git = "https://github.com/longbridge/gpui-component" }
+gpui-base = { git = "https://github.com/longbridge/gpui-component" }
 
 gix = "0.86"
 notify = "8.2"

crates/ui/Cargo.toml

@@ -17,6 +17,7 @@ graph.workspace = true
 vcs.workspace = true
 gpui.workspace = true
 gpui-component.workspace = true
+gpui-base.workspace = true
 anyhow.workspace = true
 serde.workspace = true
 serde_json.workspace = true