refactor(cache): redesign cache system with structured keys and improved performance

- Add repo_path parameter to cached_response and cached_vec_response functions
- Implement structured cache key format with namespace, repo_path, and request proto
- Replace global cache with Moka in-memory cache using weight-based eviction
- Set 256MB memory cap with 10-minute TTL and 2-minute TTI policy
- Add metrics collection for cache operations and evictions
- Implement efficient repo-scoped invalidation using key structure
- Add detailed documentation comments explaining cache architecture
- Remove outdated dependencies and update dependency versions
- Add error handling for encoding failures in cache operations
- Optimize Vec responses with length-delimited encoding and pre-allocation

repository/objects_size.rs

@@ -9,9 +9,16 @@ impl GitBare {
             return Ok(ObjectsSizeResponse::default());
         }
 
+        const MAX_OBJECTS_SIZE_OIDS: usize = 10_000;
+        if request.oids.len() > MAX_OBJECTS_SIZE_OIDS {
+            return Err(crate::error::GitError::InvalidArgument(format!(
+                "too many oids (max {MAX_OBJECTS_SIZE_OIDS})"
+            )));
+        }
+
         let mut input = String::new();
         for oid in &request.oids {
-            crate::sanitize::validate_revision(oid)?;
+            crate::sanitize::validate_oid_hex(oid)?;
             input.push_str(oid);
             input.push('\n');
         }
@@ -49,6 +56,12 @@ impl GitBare {
                     status_code: None,
                     stderr: e.to_string(),
                 })?;
+        if !output.status.success() {
+            return Err(crate::error::GitError::CommandFailed {
+                status_code: output.status.code(),
+                stderr: String::from_utf8_lossy(&output.stderr).trim().to_string(),
+            });
+        }
 
         let stdout = String::from_utf8_lossy(&output.stdout);
         let mut sizes = Vec::new();
@@ -81,6 +94,12 @@ impl GitBare {
                 status_code: None,
                 stderr: e.to_string(),
             })?;
+        if !output.status.success() {
+            return Err(crate::error::GitError::CommandFailed {
+                status_code: output.status.code(),
+                stderr: String::from_utf8_lossy(&output.stderr).trim().to_string(),
+            });
+        }
 
         let stdout = String::from_utf8_lossy(&output.stdout);
         let size = stdout