git_ui: Show more information in the branch picker (#25359)

Final product:

![CleanShot 2025-02-26 at 9  08
17@2x](https://github.com/user-attachments/assets/e5db1932-b2c6-4b32-ab67-ef0a0d19f022)

Release Notes:

- Added more information about Git branches to the branch picker.

---------

Co-authored-by: Danilo Leal <daniloleal09@gmail.com>
Co-authored-by: Marshall Bowers <git@maxdeviant.com>
Co-authored-by: Conrad Irwin <conrad.irwin@gmail.com>

crates/git/src/repository.rs

@@ -1,4 +1,5 @@
 use crate::status::FileStatus;
+use crate::SHORT_SHA_LENGTH;
 use crate::{blame::Blame, status::GitStatus};
 use anyhow::{anyhow, Context, Result};
 use askpass::{AskPassResult, AskPassSession};
@@ -127,6 +128,12 @@ pub struct CommitDetails {
     pub committer_name: SharedString,
 }
 
+impl CommitDetails {
+    pub fn short_sha(&self) -> SharedString {
+        self.sha[..SHORT_SHA_LENGTH].to_string().into()
+    }
+}
+
 #[derive(Debug, Clone, Hash, PartialEq, Eq)]
 pub struct Remote {
     pub name: SharedString,