Onboarding channels step: a failed read says so

PR #12326. Captured on the branch's own dev server (propflow-stage), with /api/integrations/company-channels/status forced to answer 500 through Playwright page.route. Before this change the same failure dropped the customer onto the per-building picker, which is the wrong screen for a company on the company-level model.

Desktop, 1440px

Checked in the captured text: "We couldn't load this step", "Try again" and "Skip for now" are present, and none of the per-building rows ("Schedule tours…") are. The status call was hit twice (dev StrictMode).

Phone, 390px

The buttons stack with Try again on top, and nothing scrolls sideways.