Add description truncation for slash commands in CLI UI

[sestinj]

CON-4280

Summary by cubic

Truncates long slash command descriptions in the CLI UI to 80 characters with an ellipsis for cleaner, readable lists. Also updates the CLI .gitignore to ignore *.cast files.

[github-actions]

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[cubic-dev-ai]

1 issue found across 2 files

Prompt for AI agents (all 1 issues)

Understand the root cause of the following 1 issues and fix them.


<file name="extensions/cli/src/ui/SlashCommandUI.tsx">

<violation number="1" location="extensions/cli/src/ui/SlashCommandUI.tsx:13">
Slicing by code units can split surrogate pairs and render broken characters when truncating descriptions that contain emoji. Please truncate by Unicode code points instead to avoid the replacement character in the UI.</violation>
</file>

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