Recurring confusion all day: the SPA lives in an open tab until reload, so
after a gateway rebuild/update users kept seeing (and benchmarking with!) an
old interface — "where is the feature", "why are the test ids old". The meta
endpoint now carries the process start timestamp; the existing 20s health
poll compares it, and when the gateway has restarted the tab shows a fixed
banner: "The gateway was updated — this page is running an older interface"
with a one-click Reload. 2 strings in all 7 languages.