fix(cli): Add trailing newline to subcommand help output

[giner]

This prevents the shell prompt from jumping around.

Issue for this PR

Fixes #48170

Type of change

• Bug fix

What does this PR do?

Adds newlines to all help messages

How did you verify your code works?

Tested locally

Screenshots / recordings

Before

vagrant@vagrant:~$ opencode agent --help
opencode agent

manage agents

Commands:
  opencode agent create  create a new agent
  opencode agent list    list all available agents

Options:
  -h, --help        show help                                                              [boolean]
  -v, --version     show version number                                                    [boolean]
      --print-logs  print logs to stderr                                                   [boolean]
      --log-level   log level                   [string] [choices: "DEBUG", "INFO", "WARN", "ERROR"]
      --pure        run without external plugins                                           [boolean]vagrant@vagrant:~$

After

vagrant@vagrant:~$ opencode agent --help
opencode agent

manage agents

Commands:
  opencode agent create  create a new agent
  opencode agent list    list all available agents

Options:
  -h, --help        show help                                                              [boolean]
  -v, --version     show version number                                                    [boolean]
      --print-logs  print logs to stderr                                                   [boolean]
      --log-level   log level                   [string] [choices: "DEBUG", "INFO", "WARN", "ERROR"]
      --pure        run without external plugins                                           [boolean]
vagrant@vagrant:~$

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

If you do not follow this template your PR will be automatically rejected.

[github-actions]

Hey! Your PR title Add trailing newline to subcommand help output doesn't follow conventional commit format.

Please update it to start with one of:

• feat: or feat(scope): new feature
• fix: or fix(scope): bug fix
• docs: or docs(scope): documentation changes
• chore: or chore(scope): maintenance tasks
• refactor: or refactor(scope): code refactoring
• test: or test(scope): adding or updating tests

Where scope is the package name (e.g., app, desktop, opencode).

See CONTRIBUTING.md for details.

[github-actions]

Thanks for your contribution!

This PR doesn't have a linked issue. All PRs must reference an existing issue.

Please:

1. Open an issue describing the bug/feature (if one doesn't exist)
2. Add Fixes #<number> or Closes #<number> to this PR description

See CONTRIBUTING.md for details.

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍