backstage release v0.99.0

Added

• Add skills to AI chat agent.
• Add tool to fetch current user info in AI chat agent.
• Show suggestions to start with in AI chat.
• Add feature flag ai-chat-verbose-debugging to toggle reasoning and tool usage info.

Changed

• Reduce list indentation in chat responses.
• Remove feature flag experimental-data-fetching.

Fixed

• Fix Card display of the ClusterAboutCard component.
• Fix ErrorsProvider component causing constant re-renders.
• Handle MCP connection failures gracefully. See ./docs/releases/v0.99.0-changelog.md for more information.