fix: resolve hanging permission prompts in headless mode - #3522

Fix: Resolve Hanging Permission Prompts in Headless Mode

Problem

When "permissions": { "bash": "ask" } is set in opencode.json and OpenCode is run in headless mode (e.g., opencode run), the application hangs silently when a bash command is requested. This happens because there is no handler to respond to the permission.ask hook, so the process waits forever for user input that never arrives.

Solution

This PR adds a built-in CLI permission handler that uses @clack/prompts to interactively prompt the user for permission in headless and run modes. The handler is always loaded as part of the plugin system, ensuring permissions can be confirmed or denied in all environments.

Key Changes

• New: src/cli/permission-handler.ts

  • Implements createCliPermissionHandler using @clack/prompts
  • Handles permission.ask by showing a confirmation dialog and returning "allow" or "deny" based on user input

• Modified: src/plugin/index.ts

  • Integrates the CLI permission handler into the plugin system so it is always available

• New: test/cli/permission-handler.test.ts

  • Adds unit tests to verify the handler's structure and basic behavior

How It Works

1. When a tool requests permission (e.g., for bash), the permission system triggers the permission.ask hook.
2. The CLI handler prompts the user in the terminal with a clear message.
3. The user can confirm or deny the request.
4. The handler responds with "allow" or "deny", unblocking the process.

Closes #3503