fix: restore _delivery.py removed while still imported by durable delivery

src/praisonai/praisonai/bots/_delivery.py

@@ -21,6 +21,9 @@
 
 logger = logging.getLogger(__name__)
 
+# Constant for permanent error detection
+PERMANENT_ERROR_PREFIX = "Permanent error:"
+
 
 class MessageSender(Protocol):
     """Protocol for message sending implementations."""
@@ -329,7 +332,7 @@ async def deliver_with_retry(
                 logger.error(
                     f"[{platform}] Permanent delivery failure to {channel_id}: {e}"
                 )
-                return False, f"Permanent error: {last_error}"
+                return False, f"{PERMANENT_ERROR_PREFIX} {last_error}"
 
             # Check if we're out of attempts
             if attempt >= max_attempts:
@@ -509,7 +512,7 @@ async def send(
             await self.outbox.mark_sent(key)
         else:
             # Check if permanent error
-            permanent = error and "Permanent error:" in error
+            permanent = error and error.startswith(PERMANENT_ERROR_PREFIX)
             await self.outbox.mark_failed(key, error or "Unknown error", permanent=permanent)
 
         return success
@@ -555,7 +558,7 @@ async def sender(target: str, payload: Dict[str, Any]) -> bool:
             )
 
             # Preserve permanent failure information
-            if not success and error and error.startswith("Permanent error:"):
+            if not success and error and error.startswith(PERMANENT_ERROR_PREFIX):
                 raise RuntimeError(error)
 
             return success

src/praisonai/tests/unit/bots/test_delivery_imports.py

@@ -0,0 +1,26 @@
+"""Regression tests for durable delivery module wiring."""
+
+import pytest
+
+
+@pytest.mark.parametrize(
+    "attr",
+    ["DurableDelivery", "deliver_with_retry", "deliver_chunked", "DurableAdapterMixin"],
+)
+def test_bots_package_exports_delivery_symbols(attr):
+    """PR #2054 removed _delivery.py while exports still referenced it."""
+    import praisonai.bots as bots
+
+    assert hasattr(bots, attr)
+    assert getattr(bots, attr) is not None
+
+
+def test_durable_adapter_imports_delivery_class():
+    from praisonai.bots._durable_adapter import DurableAdapterMixin
+    from praisonai.bots._delivery import DurableDelivery
+
+    mixin = DurableAdapterMixin()
+    mixin.setup_durable_delivery(outbox_path=None, platform="test")
+    assert mixin.durable_delivery is None
+
+    assert DurableDelivery is not None