Optimize Store persistence by eliminating deep clone of internal lock, and optimize relation merging by using retain deduplication.

server/src/state.rs

@@ -31,12 +31,9 @@ pub struct MemoryState {
 }
 
 impl MemoryState {
-    pub fn unique_items<T: Eq + std::hash::Hash + Clone>(input: Vec<T>) -> Vec<T> {
+    pub fn deduplicate<T: Eq + std::hash::Hash + Clone>(input: &mut Vec<T>) {
         let mut keys = std::collections::HashSet::new();
-        input
-            .into_iter()
-            .filter(|entry| keys.insert(entry.clone()))
-            .collect()
+        input.retain(|entry| keys.insert(entry.clone()));
     }
 
     pub fn broadcast_activity(&self, message: &str) {