Switch worker to the Ookla CLI (jitter, packet loss, server, ISP,
shareable result URL, bytes). Migration 028 enriches speedtest_results
+ adds a generic app_settings store. New /speedtest page: KPIs,
throughput + latency charts, window stats, configurable schedule
(reschedulable cron) & low-speed alert threshold, history table.
SV card gains ping/jitter + a link through to the page.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>