Monitor Kiro CLI with FrontierStack

Kiro CLI is AWS's Kiro coding agent for the terminal, with custom agents and steering files. FrontierStack detects kiro-cli and its version on this Mac or over SSH and links the official installer. The MCP pane adds FrontierStack's credential-free bridge to ~/.kiro/settings/mcp.json, which the Kiro CLI and the Kiro IDE share (or $KIRO_HOME). No tool is auto-approved, so Kiro asks before each FrontierStack call.