Functional parity with linux

lib/reactivity/src/reactor.rs

@@ -282,6 +282,14 @@ impl Reactor {
         self.inner.ensure_flush_scheduled();
     }
 
+    /// Flushes currently queued reactive jobs immediately on the calling thread.
+    ///
+    /// This is useful when host integrations need synchronous propagation
+    /// (for example, during native resize loops).
+    pub fn flush_now(&self) {
+        Rc::clone(&self.inner).flush_jobs();
+    }
+
     pub(crate) fn allocate_node(&self) -> NodeId {
         let raw = self.inner.next_node.get();
         self.inner.next_node.set(raw.wrapping_add(1));