feat(tree): add recent commit metadata and LFS support to file metadata

- Added RecentCommit message definition with oid, subject and timestamp fields
- Extended TreeEntry, Tree, and FileMetadata messages with is_lfs and recent_commit fields
- Updated get_file_metadata function to include recent commit information
- Added tree module import and recent_commit lookup functionality
- Updated protobuf definitions to include new metadata fields
- Enhanced file metadata response with LFS status and commit history

tree/mod.rs

@@ -2,3 +2,49 @@ pub mod find_files;
 pub mod get_file_metadata;
 pub mod get_tree;
 pub mod list_tree;
+
+use crate::bare::GitBare;
+use crate::pb::{self, RecentCommit, object_selector};
+
+pub(crate) fn resolve_revision(sel: &Option<pb::ObjectSelector>) -> String {
+    match sel.as_ref().and_then(|s| s.selector.as_ref()) {
+        Some(object_selector::Selector::Oid(oid)) => oid.hex.clone(),
+        Some(object_selector::Selector::Revision(name)) => name.revision.clone(),
+        None => "HEAD".into(),
+    }
+}
+
+pub(crate) fn recent_commit(gb: &GitBare, revision: &str, path: &str) -> Option<RecentCommit> {
+    let output = std::process::Command::new("git")
+        .args([
+            "--git-dir",
+            &gb.bare_dir.to_string_lossy(),
+            "log",
+            "-1",
+            "--format=%H %s %at",
+            revision,
+            "--",
+            path,
+        ])
+        .output()
+        .ok()?;
+    if !output.status.success() {
+        return None;
+    }
+    let line = String::from_utf8_lossy(&output.stdout).trim().to_string();
+    if line.is_empty() {
+        return None;
+    }
+    let (hex, rest) = line.split_once(' ')?;
+    let (subject, ts_str) = rest.rsplit_once(' ')?;
+    let ts: i64 = ts_str.parse().ok()?;
+    Some(RecentCommit {
+        oid: Some(gb.oid_to_pb(hex)),
+        subject: subject.to_string(),
+        committed_timestamp: ts,
+    })
+}
+
+pub(crate) fn is_lfs_pointer(data: &[u8]) -> bool {
+    data.starts_with(b"version https://git-lfs.github.com/spec/v1")
+}