Integrate the stats feature onto main: live mesh KPIs, observations
time-series, payload/node-type donuts, top-nodes/observers leaderboards,
radio presets, scope stats, and per-observer telemetry (battery, airtime,
noise, queue, receive errors) with 1h/6h/24h bucketing.
- adapt to the multi-IATA region model (useRegion -> single iata for /stats/*)
- rename stats getScopes -> getStatsScopes (avoids /scopes name-list collision)
- donut legend kept right but scrollable + truncating so it never clips
- balanced mesh grid; observer empty-state for telemetry-less observers
- normalize telemetry t to ms (raw path emits seconds, bucketed emits ms)
- add echarts 5.5.1; lazy-load StatsOverview chunk
MrAlders0n