Fix CI failures: update workflow demo paths and listener defaults

- Update ci.yml demo paths: use_cases/preference_based_routing →
  llm_routing/preference_based_routing, samples_python/currency_exchange
  → advanced/currency_exchange
- Fix SocketAddressValidationError in Envoy config: set default address
  ("0.0.0.0") and timeout ("30s") on array-style listener dicts so the
  Envoy template renders valid listener addresses
- Also extract prompt_gateway_listener from type: "prompt" listeners
  in the array format (was only handled for legacy dict format)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

cli/planoai/utils.py

@@ -147,6 +147,10 @@ def convert_legacy_listeners(
 
     model_provider_set = False
     for listener in listeners:
+        # Ensure address and timeout defaults for all listeners
+        listener.setdefault("address", "0.0.0.0")
+        listener.setdefault("timeout", "30s")
+
         if listener.get("type") == "model":
             if model_provider_set:
                 raise ValueError(
@@ -155,6 +159,8 @@ def convert_legacy_listeners(
             listener["model_providers"] = model_providers or []
             model_provider_set = True
             llm_gateway_listener = listener
+        elif listener.get("type") == "prompt":
+            prompt_gateway_listener = listener
     if not model_provider_set:
         listeners.append(llm_gateway_listener)