Fix id generation issue

Author: JC-386

sdk/agentserver/Azure.AI.AgentServer.AgentFramework/CHANGELOG.md

@@ -1,14 +1,9 @@
 # Release History
 
-## 1.0.0-beta.4 (Unreleased)
-
-### Features Added
-
-### Breaking Changes
+## 1.0.0-beta.4 (2025-11-11)
 
 ### Bugs Fixed
-
-### Other Changes
+- Id generation issue
 
 ## 1.0.0-beta.3 (2025-11-10)
 

sdk/agentserver/Azure.AI.AgentServer.Contracts/CHANGELOG.md

@@ -1,14 +1,9 @@
 # Release History
 
-## 1.0.0-beta.4 (Unreleased)
-
-### Features Added
-
-### Breaking Changes
+## 1.0.0-beta.4 (2025-11-11)
 
 ### Bugs Fixed
-
-### Other Changes
+- Id generation issue
 
 ## 1.0.0-beta.3 (2025-11-10)
 

sdk/agentserver/Azure.AI.AgentServer.Core/CHANGELOG.md

@@ -1,14 +1,9 @@
 # Release History
 
-## 1.0.0-beta.4 (Unreleased)
-
-### Features Added
-
-### Breaking Changes
+## 1.0.0-beta.4 (2025-11-11)
 
 ### Bugs Fixed
-
-### Other Changes
+- Id generation issue
 
 ## 1.0.0-beta.3 (2025-11-10)
 

sdk/agentserver/Azure.AI.AgentServer.Core/src/Common/Id/FoundryIdGenerator.cs

@@ -152,8 +152,8 @@ private static string ExtractPartitionId(string id, int stringLength = 32, int p
             throw new ArgumentException($"Id '{id}' does not contain a valid id.", nameof(id));
         }
 
-        // get last partitionKeyLength characters from the last part as the partition key
-        var partitionId = parts[1][^partitionKeyLength..];
+        // get first partitionKeyLength characters from the last part as the partition key
+        var partitionId = parts[1][..partitionKeyLength];
         return partitionId;
     }
 }