v2.6.2

Fix: top view showed the plain per-core grid instead of P/E grouping

The grouping keyed off cpu.topology's Gauge (the distinct-core-type count), but per-core metrics ride the protobuf per_core oneof — so the Gauge is dropped on the wire and the dashboard received it as 0, falling back to the unlabelled grid on every host.

It now derives the type count from the PerCore slice, which does cross the wire. Worked locally (--once) and in unit tests because the Gauge is set in-process; only the wire round-trip lost it. The cpu clusters: power line was never affected.

Update the heimdall-dashboard binary on the machine you watch from.