fix: verify SMTP TLS in send_message_tool

Add regression coverage for the standalone email send path and pass an explicit default SSL context to STARTTLS for certificate verification, matching the gateway email adapter hardening salvaged from PR #994.

tools/send_message_tool.py

@@ -9,6 +9,7 @@ import json
 import logging
 import os
 import re
+import ssl
 import time
 
 logger = logging.getLogger(__name__)
@@ -432,7 +433,7 @@ async def _send_email(extra, chat_id, message):
         msg["Subject"] = "Hermes Agent"
 
         server = smtplib.SMTP(smtp_host, smtp_port)
-        server.starttls()
+        server.starttls(context=ssl.create_default_context())
         server.login(address, password)
         server.send_message(msg)
         server.quit()