Fix run-template:get crash on missing fields option resolution

[Copilot]

run-template:get could fail with an internal Symfony option error (The "fields" option does not exist.), including with --format=json, even when the run template record existed. This made single-record inspection unreliable and forced users to fall back to run-template:list + client-side filtering.

• Command runtime hardening (run-template:get)

  • Guarded fields access with hasOption('fields') before calling getOption('fields').
  • Prevents command execution from crashing if option resolution differs across runtime/package contexts.

• Regression coverage (RunTemplateTest)

  • Added an explicit assertion that run-template:get defines the --fields option, so option-definition regressions are caught early.

$fields = $input->hasOption('fields') ? $input->getOption('fields') : null;