Function intent

intent(argv: string[]): CliIntent
Pre-detect a --help / -h / --version / -V request in argv, plus the first recognized subcommand if any. Runs before parseCommand so the help/version intents short-circuit without going through the option parser (which would reject --help as an unknown option in every subcommand).

The "first recognized subcommand wins" rule means issue_tree bogus --help resolves to top-level help (the bad subcommand is ignored when help is requested), while issue_tree scan --help resolves to scan-specific help.

--version / -V outrank --help / -h when both appear in the same argv, matching the de-facto convention of every major CLI.
Parameters
- argv: string[]
  arguments after the node/script entries
Returns CliIntent
the user's intent
Example
```
intent(['--help'])              // => { kind: 'help', subcommand: undefined }
  intent(['scan', '--help'])      // => { kind: 'help', subcommand: 'scan' }
  intent(['--version'])           // => { kind: 'version' }
  intent(['render', '--out', 'g.svg'])  // => { kind: 'run' }
```
- Defined in cli/issue-tree.ts:929