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- Remove outdated dependencies and update dependency versions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

tests/cluster_test.rs

@@ -1,89 +0,0 @@
-#[cfg(test)]
-mod cluster_test {
-    use gitks::pb::{
-        CreateBranchRequest, GetRepositoryRequest, InitRepositoryRequest, ObjectName,
-        ObjectSelector, RepositoryHeader, branch_service_client::BranchServiceClient,
-        object_selector, repository_service_client::RepositoryServiceClient,
-    };
-
-    const N1: &str = "http://localhost:50051";
-    const N2: &str = "http://localhost:50052";
-    const N3: &str = "http://localhost:50053";
-
-    fn hdr(path: &str) -> RepositoryHeader {
-        RepositoryHeader {
-            storage_name: String::new(),
-            relative_path: path.into(),
-            storage_path: String::new(),
-        }
-    }
-
-    #[tokio::test]
-    async fn test_cluster_routing() {
-        let ts = std::time::SystemTime::now()
-            .duration_since(std::time::UNIX_EPOCH)
-            .unwrap()
-            .as_secs();
-        let repo = format!("cluster-test-{ts}");
-
-        // ── Init via node1 ──
-        let mut n1 = RepositoryServiceClient::connect(N1).await.unwrap();
-        let r = n1
-            .init_repository(tonic::Request::new(InitRepositoryRequest {
-                repository: Some(hdr(&repo)),
-                bare: true,
-                object_format: 0,
-                initial_branch: "main".into(),
-            }))
-            .await
-            .unwrap()
-            .into_inner();
-        println!("✅ n1 init: bare={}", r.bare);
-
-        // ── Read via node2 (should forward to PRIMARY n1) ──
-        let mut n2 = RepositoryServiceClient::connect(N2).await.unwrap();
-        let r2 = n2
-            .get_repository(tonic::Request::new(GetRepositoryRequest {
-                repository: Some(hdr(&repo)),
-            }))
-            .await
-            .unwrap()
-            .into_inner();
-        println!("✅ n2 get routed→primary: bare={}", r2.bare);
-
-        // ── Read via node3 ──
-        let mut n3 = RepositoryServiceClient::connect(N3).await.unwrap();
-        let r3 = n3
-            .get_repository(tonic::Request::new(GetRepositoryRequest {
-                repository: Some(hdr(&repo)),
-            }))
-            .await
-            .unwrap()
-            .into_inner();
-        println!("✅ n3 get routed→primary: bare={}", r3.bare);
-
-        // ── Write (create branch) via node2 → primary ──
-        let mut n2b = BranchServiceClient::connect(N2).await.unwrap();
-        let b = n2b
-            .create_branch(tonic::Request::new(CreateBranchRequest {
-                repository: Some(hdr(&repo)),
-                name: "feature/x".into(),
-                start_point: Some(ObjectSelector {
-                    selector: Some(object_selector::Selector::Revision(ObjectName {
-                        revision: "main".into(),
-                    })),
-                }),
-                force: false,
-            }))
-            .await;
-        match b {
-            Ok(branch) => println!(
-                "✅ n2 create-branch routed→primary: name={}",
-                branch.into_inner().name
-            ),
-            Err(e) => println!("⚠️  create-branch: {e} (expected — empty repo has no commits)"),
-        }
-
-        println!("\n🎉 Cluster routing verified: init/read/write all proxied to PRIMARY");
-    }
-}

tests/oid_test.rs

@@ -31,6 +31,12 @@ fn test_hex_to_bytes_invalid_hex() {
     assert!(result.is_err());
 }
 
+#[test]
+fn test_hex_to_bytes_non_ascii_does_not_panic() {
+    let result = hex_to_bytes("aéx");
+    assert!(result.is_err());
+}
+
 #[test]
 fn test_hex_to_bytes_with_whitespace() {
     let bytes = hex_to_bytes("  abcd  ").unwrap();

tests/snapshot_test.rs

@@ -140,3 +140,17 @@ fn test_local_snapshot_storage_delete() {
     // Delete non-existent
     assert!(storage.delete_snapshot("nonexistent").is_err());
 }
+
+#[test]
+fn test_local_snapshot_storage_rejects_traversal_id() {
+    let dir = tempfile::tempdir().unwrap().path().to_path_buf();
+    let storage = LocalSnapshotStorage::new(dir);
+
+    assert!(storage.read_snapshot("../escape").is_err());
+    assert!(storage.delete_snapshot("../escape").is_err());
+    assert!(
+        storage
+            .write_snapshot("../escape", "repo.git", "abc123", b"data")
+            .is_err()
+    );
+}