MQTT relay_state is published inverted (HTTP /device/relay reports correctly)

[chochb]

Device / version

• Model: Shelly Wall Display XL (modelName: BLAKE, SAWD-3A1XE10EU2)
• App version: 3.26157.2133
• MQTT: enabled, HA auto-discovery on (device-based discovery)

Summary
The relay state published over MQTT (shellyelevatev2//relay_state) is inverted relative to the actual command and the physical relay. The HTTP API reports the state correctly, so the bug is isolated to the MQTT state-publishing path, not the relay logic itself.

Effect in Home Assistant
The auto-discovered switch is non-optimistic, so after a command it immediately receives the inverted state back and snaps back to the previous position. A single toggle never sticks; only a second toggle accidentally lines up.

Observed MQTT (command → reported state)

relay_command ON   → relay_state OFF
relay_command OFF  → relay_state ON

Consistent inversion across all toggles.

HTTP cross-check (correct)

> POST /device/relay {"num":0,"state":true}    → relay physically ON
> GET  /device/relay?num=0                      → {"success":true,"state":true}   # correct
> 
> POST /device/relay {"num":0,"state":false}   → relay physically OFF
> GET  /device/relay?num=0                      → {"success":true,"state":false}  # correct

HTTP command and readback both match the physical relay. Only the MQTT relay_state topic is wrong.

Expected
relay_state should publish the same logical value as the command / HTTP readback (ON→ON, OFF→OFF).

Workaround
Drive the relay via HTTP (rest_command → /device/relay) and treat the MQTT relay entity as a state source with inverted interpretation.

Likely location
Wherever the relay state is read/serialized for MQTT publishing — the value appears negated compared to the (correct) HTTP /device/relay handler.