Avoid polling after segmented light commands

[aserper]

Summary

Avoid scheduling the follow-up Platform API state poll after segmented light commands.

Segmented light entities are already configured as optimistic in Home Assistant. After a segment color/brightness command, the bridge currently schedules the same post-control poll used for whole-device commands. For segmented devices, that Platform API poll reports only a device-level light state, not per-segment state. Reconciling immediately against that simplified state can make Home Assistant and subsequent controls treat a single whole-device color as authoritative after segment updates.

This change keeps the existing per-device serialization for segment commands, but skips the post-control poll for those segment commands.

Why

Observed with a segmented Govee light device:

1. Home Assistant sends a command to a segment entity.
2. govee2mqtt sends segmentedBrightness / segmentedColorRgb through the Platform API.
3. The Platform API returns success.
4. govee2mqtt schedules a post-control poll.
5. The poll returns a single device-level DeviceState.color, not the per-segment layout.
6. That state is reconciled as the device's current light state even though the command was segment-specific.

Sanitized log excerpt:

INFO service::hass  Command for <segmented-device> segment <n>: {"state":"ON","color":{"r":...,"g":...,"b":...},"brightness":...}
INFO service::hass  Using Platform API to control <segmented-device> segment
INFO platform_api   control_device result: code=200, message="success", capability=SegmentColorSetting(instance="segmentedBrightness")
INFO platform_api   control_device result: code=200, message="success", capability=SegmentColorSetting(instance="segmentedColorRgb")
INFO service::state Polling <segmented-device> to get latest state after control
INFO service::state requesting update via Platform API <segmented-device> Some(DeviceState { color: DeviceColor { r: ..., g: ..., b: ... }, brightness: ..., source: "PLATFORM API", ... })

The important detail is that the segment commands succeed, but the immediate poll only reports a whole-device color state.

Change

• Add a Coordinator::new_without_poll constructor.
• Add State::resolve_device_for_control_without_poll to keep the serialization lock without scheduling the delayed state poll.
• Use the no-poll control path for mqtt_light_segment_command.

Whole-device commands still use the existing post-control polling behavior.

Validation

Locally passed:

cargo fmt --all -- --check
cargo test --all -- --show-output
cargo build --all