feat(server): add tracing spans and caching to archive and blame services

- Add tracing spans with repo labels for archive and blame operations
- Implement caching for archive list entries when using OID selectors
- Implement caching for blame operations when using OID selectors
- Add detailed

pack/index_pack.rs

@@ -8,15 +8,27 @@ impl GitBare {
     /// Index a pack file from streamed input.
     ///
     /// Client-streaming → unary response.
-    /// Collects all input chunks into a single pack, then runs `git index-pack`.
+    /// Writes each chunk directly to a temp file to avoid buffering
+    /// the entire pack in memory.
     pub fn index_pack(&self, inputs: Vec<IndexPackRequest>) -> GitResult<IndexPackResponse> {
-        // Reassemble all chunks into a single pack data buffer
-        let mut pack_data = Vec::new();
         let mut strict = false;
         let mut keep = false;
+        let mut has_data = false;
+
+        let pack_dir = self.bare_dir.join("objects").join("pack");
+        std::fs::create_dir_all(&pack_dir).map_err(GitError::Io)?;
+
+        // Stream pack data to a temp file instead of accumulating in memory
+        let mut tmp_file = tempfile::Builder::new()
+            .prefix("tmp_index_pack_")
+            .tempfile_in(&pack_dir)
+            .map_err(GitError::Io)?;
 
         for input in &inputs {
-            pack_data.extend_from_slice(&input.data);
+            if !input.data.is_empty() {
+                tmp_file.write_all(&input.data).map_err(GitError::Io)?;
+                has_data = true;
+            }
             if input.strict {
                 strict = true;
             }
@@ -25,25 +37,18 @@ impl GitBare {
             }
         }
 
-        if pack_data.is_empty() {
+        if !has_data {
             return Err(GitError::InvalidArgument("empty pack data".into()));
         }
 
-        let pack_dir = self.bare_dir.join("objects").join("pack");
-        std::fs::create_dir_all(&pack_dir).map_err(GitError::Io)?;
-
-        // Write pack data to a unique temp file in the pack directory.
-        let mut tmp_file = tempfile::Builder::new()
-            .prefix("tmp_index_pack_")
-            .tempfile_in(&pack_dir)
-            .map_err(GitError::Io)?;
-        tmp_file.write_all(&pack_data).map_err(GitError::Io)?;
+        // Flush and get the path before we pass it to git
+        tmp_file.flush().map_err(GitError::Io)?;
         let tmp_path = tmp_file.path().to_path_buf();
 
         let mut args = vec![
             "--git-dir".to_string(),
             self.bare_dir.to_string_lossy().into_owned(),
-            "index-pack".to_string(),
+            "index-pack".into(),
         ];
         if strict {
             args.push("--strict".into());
@@ -59,6 +64,7 @@ impl GitBare {
             .unchecked()
             .run()?;
 
+        // Drop the temp file handle — git index-pack has processed it
         drop(tmp_file);
 
         if !result.status.success() {
@@ -73,12 +79,9 @@ impl GitBare {
         let stderr = String::from_utf8_lossy(&result.stderr);
         let all_output = format!("{output}\n{stderr}");
 
-        // git index-pack outputs the .idx and .pack filenames
-        // e.g. "... pack-<hex>.pack  ...  pack-<hex>.idx"
         let pack_hash = all_output
             .lines()
             .filter_map(|line| {
-                // Look for the hash after "pack-" and before ".idx" or ".pack"
                 let trimmed = line.trim();
                 if let Some(idx) = trimmed.find("pack-") {
                     let rest = &trimmed[idx + 5..];
@@ -96,7 +99,7 @@ impl GitBare {
         // Try to get object count from .idx if it exists
         let mut object_count = 0u64;
         if let Some(ref hash) = pack_hash {
-            let idx_path = pack_dir.join(format!("pack-{}.idx", hash));
+            let idx_path = pack_dir.join(format!("pack-{hash}.idx"));
             if idx_path.exists() {
                 let verify = duct::cmd(
                     "git",

pack/pack_objects.rs

@@ -18,6 +18,10 @@ impl GitBare {
     ) -> Result<ReceiverStream<Result<PackfileChunk, tonic::Status>>, tonic::Status> {
         let bare_dir = self.bare_dir.clone();
         let bare_dir_str = bare_dir.to_string_lossy().into_owned();
+        tracing::info!(
+            repo = %bare_dir_str,
+            "spawning git pack-objects subprocess"
+        );
 
         let (tx, rx) = tokio::sync::mpsc::channel(8);
 

pack/receive_pack.rs

@@ -21,6 +21,10 @@ impl GitBare {
         + 'static,
     ) -> Result<ReceiverStream<Result<ReceivePackResponse, tonic::Status>>, tonic::Status> {
         let bare_dir = self.bare_dir.to_string_lossy().into_owned();
+        tracing::info!(
+            repo = %bare_dir,
+            "spawning git receive-pack subprocess"
+        );
 
         let (tx, rx) = tokio::sync::mpsc::channel(16);
 

pack/upload_pack.rs

@@ -21,6 +21,10 @@ impl GitBare {
         + 'static,
     ) -> Result<ReceiverStream<Result<UploadPackResponse, tonic::Status>>, tonic::Status> {
         let bare_dir = self.bare_dir.to_string_lossy().into_owned();
+        tracing::info!(
+            repo = %bare_dir,
+            "spawning git upload-pack subprocess"
+        );
 
         let (tx, rx) = tokio::sync::mpsc::channel(16);