feat(server): add SegmentedSlab collection (apache#2549)

Add a concurrent segmented slab with structural sharing,
designed for Read-Copy-Update patterns with lock-free
reads and copy-on-write modifications.

Author: hubcio

Cargo.lock

@@ -63,6 +63,7 @@ rustls = { workspace = true }
 serde = { workspace = true }
 serde_json = { workspace = true }
 serde_with = { workspace = true, features = ["base64"] }
+slab = "0.4.11"
 strum = { workspace = true }
 thiserror = { workspace = true }
 tokio = { workspace = true }

core/common/Cargo.toml

@@ -0,0 +1,20 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF licenses this file
+// to you under the Apache License, Version 2.0 (the
+// "License"); you may not use this file except in compliance
+// with the License.  You may obtain a copy of the License at
+//
+//   http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing,
+// software distributed under the License is distributed on an
+// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, either express or implied.  See the License for the
+// specific language governing permissions and limitations
+// under the License.
+
+mod segmented_slab;
+
+pub use segmented_slab::SegmentedSlab;