fix: repair --format help text in CLI

[Socialpranker]

Disclosure: this patch was prepared with AI assistance (Claude Opus 5). I checked the match arms and traced the print order in showHelp() myself before opening this.

Problem

Two things are off in the --format entry of vobject --help.

The description is split in half by another option. showHelp() prints line by line, and the continuation of the format list sits after the --forgiving line, so the actual output reads:

  --format      Convert to a specific format. Must be one of: vcard, vcard21,
  --forgiving   Makes the parser less strict.
                vcard30, vcard40, icalendar20, jcal, jcard, json, mimedir.

One accepted value is missing. The format case in parseArguments() accepts ten values:

$this->format = match ($value) {
    'jcard', 'jcal', 'vcard21', 'vcard30', 'vcard40', 'icalendar20', 'json', 'mimedir', 'icalendar', 'vcard' => $value,
    default => throw new \InvalidArgumentException('Unknown format: '.$value),
};

The help text lists nine — icalendar (without the 20 suffix) is absent, even though --format=icalendar works.

Fix

Move the continuation lines back under --format and add icalendar. The list now needs three lines to stay inside the same width as the surrounding entries, so it wraps onto mimedir. rather than being crammed in.

Resulting output:

  --format      Convert to a specific format. Must be one of: vcard, vcard21,
                vcard30, vcard40, icalendar, icalendar20, jcal, jcard, json,
                mimedir.
  --forgiving   Makes the parser less strict.

Help text only — no behaviour change.