ToolsTab: truncate longer tool descriptions for nicer rendering

[ksinder]

Motivation and Context

Small PR that improves how MCP tool descriptions are rendered in the "Tools" tab when they're relatively verbose/lengthy.

• In the list view, descriptions are truncated/ellipsized after 3 lines
• In the right pane (a specific tool), I added:
  • max-h-48 and overflow-y-auto: to limit the height of the description's "text area" shown in the window at once, and add vertical scrollbars a description is longer than that
  • whitespace-pre-wrap: To respect newline characters in descriptions [0]
  • Grey borders between the description & inputs/outputs of the tool and headings to better demarcate those

[0] I want to ideally use ReactMarkdown here for even better rendering for tools that have Markdown-friendly descriptions. But we can explore that in a future PR; I had trouble figuring out the EJS node modules setup with Jest here so I punted that work for now

How Has This Been Tested?

Ran locally and manually click tested with longer tool descriptions (our remote MCP server at Notion has a bunch of these 😅).

Before	After (long description)	After (short description)

Breaking Changes

N/A

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Documentation update

Checklist

• I have read the MCP Documentation
• My code follows the repository's style guidelines
• New and existing tests pass locally
• I have added appropriate error handling
• I have added or updated documentation as needed

Additional context

N/A for now