fix: harden execute_code cleanup and reduce logging noise

Follow-up to cherry-picked PR #1588 (aydnOktay):
- Initialize server_sock = None before try block to prevent NameError
  if exception occurs before socket creation (line 413 is inside the try)
- Guard server_sock.close() with None check
- Narrow cleanup exception handlers to OSError (the actual error type)
- Remove exc_info=True from cleanup debug logs — benign teardown
  failures don't need stack traces, the message is sufficient
- Remove redundant try/except around shutil.rmtree(ignore_errors=True)
- Silence sock_path unlink with pass — expected when already cleaned up

tools/code_execution_tool.py

@@ -395,6 +395,7 @@ def execute_code(
     tool_call_log: list = []
     tool_call_counter = [0]  # mutable so the RPC thread can increment
     exec_start = time.monotonic()
+    server_sock = None
 
     try:
         # Write the auto-generated hermes_tools module
@@ -615,19 +616,17 @@ def execute_code(
 
     finally:
         # Cleanup temp dir and socket
-        try:
-            server_sock.close()
-        except Exception as e:
-            logger.debug("Server socket close error: %s", e, exc_info=True)
-        try:
-            import shutil
-            shutil.rmtree(tmpdir, ignore_errors=True)
-        except Exception as e:
-            logger.debug("Could not clean temp dir: %s", e, exc_info=True)
+        if server_sock is not None:
+            try:
+                server_sock.close()
+            except OSError as e:
+                logger.debug("Server socket close error: %s", e)
+        import shutil
+        shutil.rmtree(tmpdir, ignore_errors=True)
         try:
             os.unlink(sock_path)
-        except OSError as e:
-            logger.debug("Could not remove socket file: %s", e, exc_info=True)
+        except OSError:
+            pass  # already cleaned up or never created
 
 
 def _kill_process_group(proc, escalate: bool = False):