Having multiline description results in assistants getting saved incorrectly and is not usable.

[sangee2004]

Version 0.10.0-rc2 (0.10.0-rc2)

Steps to reproduce the problem:

1. Create an assistant with multiline description

2. Edit the assistant . Notice that instruction is incorrect and tool settings are lost.

3. Get out of edit mode without changing anything.
4. Chat with the assistant.
   Notice that no input field is provided for chat messages to be entered.

[thedadams]

Description field should not allow multiple lines.

[thedadams]

PR: #220

[sangee2004]

Tested with electron build with commit id -523bf344b9e . We are not allowed to enter multi line description when creating assistants.