added basic network play

.copilot-rules.md

@@ -84,8 +84,9 @@ Do not introduce new build steps unless required.
   - Rendering
   - Input
   - Game simulation
-- Networking must run in a **separate thread**
-- SDL main loop must **never block** on networking
+- Networking must be **non-blocking** from the SDL main loop
+  - Either run networking on a separate thread, or poll ENet frequently with a 0 timeout
+  - Never wait/spin for remote inputs on the render thread
 - Cross-thread communication via queues or buffers only
 
 ---
@@ -113,7 +114,8 @@ Never hardcode machine-specific paths.
 
 ## Networking (COOPERATE Network Mode)
 
-Follow `network_cooperate_multiplayer.md`.
+Follow `docs/ai/cooperate_network.md`.
+If `network_cooperate_multiplayer.md` exists, keep it consistent with the canonical doc.
 
 Mandatory model:
 - **Input lockstep**