simplify: MemoryControlPlaneClient uses boto3 endpoint resolution

Remove dependency on endpoints.py. Let boto3 resolve the endpoint
natively (includes its own region validation). The
BEDROCK_AGENTCORE_CONTROL_ENDPOINT env var override is still respected.

Author: jariy17

src/bedrock_agentcore/memory/controlplane.py

@@ -13,8 +13,6 @@
 import boto3
 from botocore.exceptions import ClientError
 
-from bedrock_agentcore._utils.endpoints import _validate_endpoint_url
-
 from .constants import (
     MemoryStatus,
 )
@@ -35,11 +33,10 @@ def __init__(self, region_name: str = "us-west-2", environment: str = "prod"):
         self.region_name = region_name
         self.environment = environment
 
-        control_endpoint = os.getenv("BEDROCK_AGENTCORE_CONTROL_ENDPOINT")
         service_name = os.getenv("BEDROCK_AGENTCORE_CONTROL_SERVICE", "bedrock-agentcore-control")
         cp_kwargs: dict = {"region_name": self.region_name}
+        control_endpoint = os.getenv("BEDROCK_AGENTCORE_CONTROL_ENDPOINT")
         if control_endpoint:
-            _validate_endpoint_url(control_endpoint)
             cp_kwargs["endpoint_url"] = control_endpoint
         self.client = boto3.client(service_name, **cp_kwargs)