The dashboard.md 'Line 3: drill-in triggers' section described inline
↳ logs and ↳ build logs side-panel affordances that were removed from
the container row some time ago (navigation links were consolidated onto
the Line 1 nav strip; journal + build-log viewing moved to /logs.html).
Replace that stale section with accurate documentation of the per-agent
⋮ overflow menu (restart/stop/start/rebuild + journal-logs deep-link +
destroy/purge + deployed-sha forge link).
Also update the AGENT and SYSTEM sub-tab descriptions to cover:
- localStorage persistence of agent/unit selection across page loads
- ?agent= / ?unit= URL params for deep-linking (used by the ⋮ menu)
- 'fetched N ago' chip after each successful fetch (ticks every 30 s)