Discover SONOFF water valve as MQTT valve

[MaxRink]

Summary

Discover switch exposes as Home Assistant MQTT valve entities when ZHC expose metadata declares homeassistant: {type: "valve"}.

The object ID remains the existing switch-shaped value (switch or switch_<endpoint>), so this PR does not add an avoidable entity rename on top of the Home Assistant component/domain migration.

Why

SONOFF water valves are exposed by ZHC as on/off switch-like Zigbee devices, but they are semantically valves in Home Assistant. ZHC now carries this intent on the expose itself via withHomeAssistant, so Zigbee2MQTT can translate that generic expose metadata without hardcoding a device model.

Review note

Koenkk flagged that changing the Home Assistant component and the object ID together would be breaking for users. This PR stays narrow and keeps the object ID stable, so only the HA component mapping changes here.

Validation

Local validation in /private/tmp/z2m-valve-discovery:

• node --run check
• node --run test -- test/extensions/homeassistant.test.ts -t "MQTT valve"
• node --run build
• git diff --check origin/dev...HEAD

Paired work

• ZHC already marks the SONOFF valve on/off exposes with homeassistant: {type: "valve"}.

[Koenkk]

Given that the object_id changes, I believe this is a breaking change?

[MaxRink]

Yes, changing the Home Assistant discovery component from switch to valve is still a migration to call out.

I adjusted the implementation so the old object ID shape is preserved (switch / switch_<endpoint>). That avoids an extra entity rename on top of the intended component/domain change.

[Koenkk]

• Can you verify that with this change no new entity is created?
• I would prefer to introduce a more generic mechanism to change HA expose properties (e.g. directly on the expose itself in zhc instead of on meta)

[Koenkk]

Im wondering if we maybe can just do this through the override ha discovery payload which already exists in zhc?