Update UpdatedProcess with UserDiff

src/api.rs

@@ -106,8 +106,9 @@ pub struct UserDiff {
 pub struct UpdatedProcess {
     pub commitment_tx: OutPoint,
     pub current_process: Process,
-    pub new_state: Option<ProcessState>,
-    pub modified_state: Option<(ProcessState, ProcessState)>, // first the previous state, then the current one
+    pub new_diffs: Vec<UserDiff>, // All diffs should have the same new_state_merkle_root
+    pub modified_state: Option<String>, // basically when we add/receive validation proofs for a state
+    // I think we should never have both new_state and modified_state
 }
 
 #[derive(Debug, PartialEq, Tsify, Serialize, Deserialize, Default)]