Describe the bug
In the most simple terms, whenever I begin a new chat and get it to use any MCP server it works fine for the first message, then any future messages immediately cause the chat to crash and the app is unable to read any of the data from the chat even in history.

To Reproduce
Steps to reproduce the behavior:

1. Go to Home and start a new chat as normal, making sure that you have some MCP servers enabled.
2. Ask it something to get it to use an MCP server, does not matter which one.
3. Try to send any message to the chat as usual.
4. Chat is unable to work and immediately crashes when sent, immediately throwing the error

Failed to Load Session
Stream error: Failed to read session: data did not match any variant of untagged enum ResultFormat at line 1 column 141

Expected behavior
I expect the chat to continue as normal and not instantly crash or whatever is happening

Removed Knowledgegraphmemory to get it to use another server
https://github.com/user-attachments/assets/d8667fd8-6d17-4f7e-b33e-b0a68b12bfe1

Screenshots

Please provide the following information

• OS & Arch: MacOS 26.2 (25C56) Apple M2
• Interface: UI
• Version: 1.18.0
• Extensions enabled: ChatRecall, Filesystem, Knowledgegraphmemory, Memory & Thinktool
• Provider & Model: Github Copilot – claude-sonnet-4