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

server/repository_maint.rs

@@ -10,19 +10,32 @@ pub(crate) fn maintenance_response(out: std::process::Output) -> RepositoryMaint
     }
 }
 
-fn dir_size(path: &std::path::Path) -> u64 {
-    let mut total = 0u64;
-    if let Ok(entries) = std::fs::read_dir(path) {
-        for entry in entries.flatten() {
-            let p = entry.path();
-            if p.is_file() {
-                total += entry.metadata().map(|m| m.len()).unwrap_or(0);
-            } else if p.is_dir() {
-                total += dir_size(&p);
-            }
+/// Get approximate repository size using git count-objects instead of
+/// recursively scanning the filesystem (which is O(n) and very slow for large repos).
+fn dir_size(gb: &crate::bare::GitBare) -> u64 {
+    let out = git_cmd(gb, &["count-objects", "-v"]).ok();
+    let text = out
+        .as_ref()
+        .map(|o| String::from_utf8_lossy(&o.stdout).into_owned())
+        .unwrap_or_default();
+
+    let mut loose_size_kb = 0u64;
+    let mut pack_size_kb = 0u64;
+    let mut garbage_size_kb = 0u64;
+
+    for line in text.lines() {
+        let line = line.trim();
+        if let Some(val) = line.strip_prefix("size: ") {
+            loose_size_kb = val.trim().parse().unwrap_or(0);
+        } else if let Some(val) = line.strip_prefix("size-pack: ") {
+            pack_size_kb = val.trim().parse().unwrap_or(0);
+        } else if let Some(val) = line.strip_prefix("size-garbage: ") {
+            garbage_size_kb = val.trim().parse().unwrap_or(0);
         }
     }
-    total
+
+    // count-objects reports sizes in KiB; convert to bytes
+    (loose_size_kb + pack_size_kb + garbage_size_kb) * 1024
 }
 
 fn count_refs(gb: &crate::bare::GitBare) -> u64 {
@@ -44,7 +57,7 @@ fn file_len(path: &std::path::Path) -> u64 {
 }
 
 pub(crate) fn get_statistics(gb: &crate::bare::GitBare) -> RepositoryStatistics {
-    let size_bytes = dir_size(&gb.bare_dir);
+    let size_bytes = dir_size(gb);
 
     let mut loose_object_count: u64 = 0;
     let mut packed_object_count: u64 = 0;
@@ -81,6 +94,11 @@ pub(crate) fn check_health(
     gb: &crate::bare::GitBare,
     connectivity_only: bool,
 ) -> Result<RepositoryHealthResponse, tonic::Status> {
+    tracing::info!(
+        repo = %gb.bare_dir.display(),
+        connectivity_only = connectivity_only,
+        "running health check"
+    );
     let mut args: Vec<&str> = vec!["fsck"];
     if connectivity_only {
         args.push("--connectivity-only");
@@ -109,6 +127,12 @@ pub(crate) fn run_gc(
     prune: bool,
     aggressive: bool,
 ) -> Result<RepositoryMaintenanceResponse, tonic::Status> {
+    tracing::info!(
+        repo = %gb.bare_dir.display(),
+        prune = prune,
+        aggressive = aggressive,
+        "running garbage collection"
+    );
     let mut args: Vec<&str> = vec!["gc"];
     if prune {
         args.push("--prune=now");
@@ -126,6 +150,13 @@ pub(crate) fn run_repack(
     write_bitmaps: bool,
     write_multi_pack_index: bool,
 ) -> Result<RepositoryMaintenanceResponse, tonic::Status> {
+    tracing::info!(
+        repo = %gb.bare_dir.display(),
+        full = full,
+        write_bitmaps = write_bitmaps,
+        write_multi_pack_index = write_multi_pack_index,
+        "running repack"
+    );
     let mut args: Vec<&str> = vec!["repack", "-d"];
     if full {
         args.push("-a");
@@ -145,6 +176,12 @@ pub(crate) fn run_commit_graph_write(
     split: bool,
     replace: bool,
 ) -> Result<RepositoryMaintenanceResponse, tonic::Status> {
+    tracing::info!(
+        repo = %gb.bare_dir.display(),
+        split = split,
+        replace = replace,
+        "writing commit-graph"
+    );
     let mut args: Vec<&str> = vec!["commit-graph", "write"];
     if split {
         args.push("--split");