Read Teslemetry energy sensors from a local Powerwall

[Bre77]

Proposed change

First rung of the local Powerwall data-reading stack for Teslemetry, on top of the local-control base (home-assistant#176969).

A paired energy site gains a dedicated local-first live coordinator. The nine locally supported energy live sensors — solar power, energy left, total pack energy, percentage charged, battery power, load power, grid power, generator power and island status — are pointed at it, so on a paired site they read from the LAN gateway with cloud fallback. An unpaired site is unchanged and keeps using the cloud live coordinator.

The separate cloud live coordinator still serves the cloud-only live entities (grid-services power, wall connectors). Because the two coordinators are independent, a local success never overwrites the cloud-only fields with None, and a cloud outage leaves the nine local sensors available while the cloud-only entities correctly go unavailable. One shared snapshot serves all nine entities per refresh — there is no per-entity gateway request. No entities are added.

Type of change

• Dependency upgrade
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