feat: Agent Chat CLI v2

[damassi]

This adds a lot of significant functionality, notably:

• Dynamic MCP server selection via inference, and lazy init. This saves tokens by connecting to only whats needed for the users query, and only sending up whats needed for the question, which is useful when dealing with complex agents with lots of tools and large prompts
• Better notifications
• Better session management in MCP client / server, and support for reestablishing connections
• Lots of bug fixes and polish
• Support for claude subagents
• Support for fetching remote prompts

agent-cli.mp4