Add enhanced member join and leave events

contracts/sorosave/src/group.rs

@@ -74,11 +74,14 @@ pub fn join_group(env: &Env, member: Address, group_id: u64) -> Result<(), Contr
     }
 
     group.members.push_back(member.clone());
+    let member_count = group.members.len();
     storage::set_group(env, &group);
     storage::add_member_group(env, &member, group_id);
 
-    env.events()
-        .publish((crate::symbol_short!("grp_join"),), (group_id, member));
+    env.events().publish(
+        (crate::symbol_short!("mem_join"),),
+        (group_id, member, env.ledger().timestamp(), member_count),
+    );
 
     Ok(())
 }
@@ -112,11 +115,14 @@ pub fn leave_group(env: &Env, member: Address, group_id: u64) -> Result<(), Cont
     }
 
     group.members = new_members;
+    let member_count = group.members.len();
     storage::set_group(env, &group);
     storage::remove_member_group(env, &member, group_id);
 
-    env.events()
-        .publish((crate::symbol_short!("grp_leav"),), (group_id, member));
+    env.events().publish(
+        (crate::symbol_short!("mem_leav"),),
+        (group_id, member, env.ledger().timestamp(), member_count),
+    );
 
     Ok(())
 }

contracts/sorosave/src/test.rs

@@ -222,3 +222,23 @@ fn test_set_group_admin() {
     let group = client.get_group(&group_id);
     assert_eq!(group.admin, new_admin);
 }
+
+#[test]
+fn test_member_join_leave_events() {
+    let (env, admin, client, token) = setup_env();
+    let group_id = create_test_group(&env, &client, &admin, &token);
+
+    let member1 = Address::generate(&env);
+
+    // Join event should include group_id, member, timestamp, and member_count
+    client.join_group(&member1, &group_id);
+
+    let group = client.get_group(&group_id);
+    assert_eq!(group.members.len(), 2); // admin + member1
+
+    // Leave event should include group_id, member, timestamp, and updated member_count
+    client.leave_group(&member1, &group_id);
+
+    let group = client.get_group(&group_id);
+    assert_eq!(group.members.len(), 1); // only admin remains
+}