fix(cli): avoid node util styleText dependency in setup wizard

[freelanceagent1]

Summary

Fixes the aft-opencode setup / doctor CLI crash on older Node runtimes where node:util.styleText is unavailable.

The failure reported was:

$ bunx @cortexkit/aft-opencode@latest setup
SyntaxError: The requested module 'node:util' does not provide an export named 'styleText'

Cause

The CLI prompt path depended on @clack/prompts, which pulled in a runtime path that expected newer Node node:util exports than are available on Node 19.9.0.

Fix

• replace the CLI prompt wrapper with a small Node-native implementation
• remove @clack/prompts from the plugin package dependencies
• keep the existing setup / doctor CLI behavior intact

Validation

• bun install
• bun run build in packages/opencode-plugin
• node packages/opencode-plugin/dist/cli.js

Additionally, the built dist/cli.js no longer contains:

• styleText
• stripVTControlCharacters
• @clack/prompts
• node:util

Compatibility note

• validated on the current Windows host by rebuilding and running the bundled CLI
• this change is intended to improve compatibility for older Node runtimes, including the reported macOS arm64 Node 19.9.0 case
• I did not runtime-test on macOS in this branch from this machine