`is True` strict identity fails if the NHL API returns an integer 1
instead of a JSON boolean. A truthy check is safe here since the
Intermission field is always False/0 for non-intermission live games.
Also adds a test that verifies intermission games are separated from
live games in the /scoreboard response.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
