agent list prints every agent's full resolved permission rules (8,600+ lines) instead of an inventory

Description

opencode agent list pretty-prints every agent's fully expanded inherited permission ruleset, one giant block per agent. On this setup that is 8,634 lines / 222 KB for a routine inventory question. The size makes the command hard to use directly and overflows the output limits of coding-agent harnesses that shell out to it, which is how we keep hitting it.

A one-line summary per agent (name, model, description) with the full resolved ruleset behind a --verbose flag would cover both needs. opencode debug agent <name> already gives the per-agent detail and is what we use as the workaround.

Happy to put up a small PR if you confirm which direction you'd prefer.

OpenCode version

1.18.23 (brew tap, macOS; behavior unchanged since at least 1.18.4, and packages/opencode/src/cli/cmd/agent.ts's list handler hasn't changed on dev since June)

Steps to reproduce

1. Have a config with a normal handful of agents
2. opencode agent list | wc -cl
3. Observe ~8,600 lines / ~222 KB of expanded permission rules