Agent Runs observability hits CLI; list, inspect, trace, projects

Minor Changes

• b9e4f06: Add a vercel agent-runs command for Agent Runs observability: list lists Agent Runs for a project, inspect <runId> shows run metadata, events, usage, and subagents, trace <runId> shows the full trace (turns, messages, reasoning, and tool calls), and projects lists projects in the team with Agent Runs activity. All subcommands support --json for machine-readable output.