Get performance metrics for get_wd_tree()

It's a tiny little function, but I think it can be slow
as it could incur a lot of work, scaling up with the size
of the repository, and the amount of untracked data in it.

Let's gather some data.

crates/gitbutler-core/src/git/mod.rs

@@ -38,7 +38,7 @@ mod url;
 pub use self::url::*;
 
 mod repository_ext;
-pub use repository_ext::*;
+pub use repository_ext::RepositoryExt;
 
 mod tree_ext;
 pub use tree_ext::*;

crates/gitbutler-core/src/git/repository_ext.rs

@@ -1,14 +1,17 @@
 use anyhow::Result;
 use git2::{Repository, Tree};
+use tracing::instrument;
 
 /// Extension trait for `git2::Repository`.
 ///
 /// For now, it collects useful methods from `gitbutler-core::git::Repository`
 pub trait RepositoryExt {
+    /// Based on the index, add all data similar to `git add .` and create a tree from it, which is returned.
     fn get_wd_tree(&self) -> Result<Tree>;
 }
 
 impl RepositoryExt for Repository {
+    #[instrument(level = tracing::Level::DEBUG, skip(self), err(Debug))]
     fn get_wd_tree(&self) -> Result<Tree> {
         let mut index = self.index()?;
         index.add_all(["*"], git2::IndexAddOption::DEFAULT, None)?;

crates/gitbutler-core/src/project_repository/repository.rs

@@ -615,8 +615,7 @@ impl Repository {
     }
 
     pub fn repo(&self) -> &git2::Repository {
-        let r = &self.git_repository;
-        r.into()
+        (&self.git_repository).into()
     }
 }