Add Terncy WS01 wall switch variants

[calvinastroboy]

Add support for Terncy/Xiaoyan TERNCY-WS01 wall switches

Adds Zigbee2MQTT definitions for:

• TERNCY-WS01-S1, TERNCY-WS01-S2, TERNCY-WS01-S3, TERNCY-WS01-S4
• TERNCY-WS01-D1, TERNCY-WS01-D2, TERNCY-WS01-D3, TERNCY-WS01-D4

The devices use manufacturer Xiaoyan, manufacturer code 0x1228, and
private cluster 0xfccc.

Standard relay support

The gateway node-struct corpus shows the following standard genOnOff relay
endpoints:

Models	Relay exposes
WS01-S1, WS01-D1	state_l1
WS01-S2, WS01-D2	state_l1, state_l2
WS01-S3, WS01-D3	state_l1, state_l2, state_l3
WS01-S4, WS01-D4	state_l1, state_l2, state_l3, state_l4

All models have four private endpoints, so action parsing is retained for
l1 through l4, including non-relay input endpoints.

Private features

The converter carries the existing Terncy wall-switch protocol mapping:

• operation mode through private command 0x1d (control_relay=0,
  wireless=1);
• wireless-mode LED state through command 0x1f (off=0, on=1);
• relay-mode LED feedback through attr 0x001f, written from source endpoint
  110 (positive=0, negative=1);
• raw action frames for 1-7 clicks, hold, release, and action duration.

The upstream definition intentionally excludes the community-only
relay_enabled, relay_constant_power, and button_relay_binding convenience
controls. Command 0x13 and attr 0x0026 are not used as LED feedback paths.

Validation

The repository test added with this change covers all eight model IDs, each
relay endpoint boundary, all four endpoint action names, and a click frame from
a non-relay endpoint. The tests pass locally.

The endpoint layout is supported by gateway node-struct evidence. I do not have
a live WS01 packet-validation record in this change, so the private behavior is
reported as family-based inference from the verified WS07-D3 implementation and
should be confirmed on live WS01 hardware.

Related image PR

The matching device images are prepared in zigbee2mqtt.io PR #5322.