core: `ToolMessage.status` is not preserved by `core.messages.utils.convert_to_messages`

### Checked other resources - [x] This is a bug, not a usage question. For questions, please use the LangChain Forum (https://forum.langchain.com/). - [x] I added a clear and descriptive title that summarizes this issue. - [x] I used the GitHub search to find a similar question and didn't find it. - [x] I am sure that this is a bug in LangChain rather than my code. - [x] The bug is not resolved by updating to the latest stable version of LangChain (or the specific integration package). - [x] I read what a minimal reproducible example is (https://stackoverflow.com/help/minimal-reproducible-example). - [x] I posted a self-contained, minimal, reproducible example. A maintainer can copy it and run it AS IS. ### Example Code We expect that `convert_to_messages` should reverse the `model_dump` operation on a ToolMessage: ```python from langchain_core.messages import convert_to_messages, ToolMessage tool_message = ToolMessage(content="Error: please fix your mistakes", tool_call_id="foobar", status="error") tool_message_json = tool_message.model_dump() tool_message_recovered = convert_to_messages([tool_message_json])[0] # AssertionError: received "success", expected "error" assert tool_message.status == tool_message_recovered.status, 'received "%s", expected "%s"' % (tool_message_recovered.status, tool_message.status) ``` ### Error Message and Stack Trace (if applicable) _No response_ ### Description - I'm storing langchain messages as JSONB in a postgres database, using `message.model_dump()` - I expect that `convert_to_messages` should recover the original message - Instead, the `ToolMessage.status` receives the default value of "success" rather than the value in the database. ### System Info System Information ------------------ > OS: Linux > OS Version: #1 SMP PREEMPT_DYNAMIC Sun Mar 30 16:01:29 UTC 2025 > Python Version: 3.12.11 (main, Jun 4 2025, 08:56:18) [GCC 11.4.0] Package Information ------------------- > langchain_core: 0.3.75 > langchain: 0.3.27 > langsmith…