feat(displays): per-display devices + DDC/CI capability entities

Restructure how displays are exposed in Home Assistant:

Each physical monitor is now its own HA device linked to the media-server
hub via `via_device`. The hub keeps the media_player + script buttons; per-
display devices hold the power switch, brightness slider, and the new
capability entities. This lets users place displays in their own area/room
and keeps related entities grouped together in the UI.

New platforms:
- sensor: DisplayResolutionSensor (diagnostic, from EDID)
- binary_sensor: DisplayPrimaryBinarySensor + DisplayPowerControlBinarySensor
  (both diagnostic; help users see why a power switch is or isn't created)
- select: DisplayInputSourceSelect (HDMI1/DP1/...), DisplayColorPresetSelect
  (color temperature), DisplayPictureModeSelect (VCP 0xDC scene modes)
- number: added DisplayContrastNumber alongside brightness

Other changes:
- display_device helper centralises the per-display DeviceInfo; pulls real
  manufacturer/model from EDID; device name no longer prepends the hub
  title since via_device already shows the hierarchy.
- api_client gains set_display_{contrast,input_source,color_preset,picture_mode}
  and stops forcing `?refresh=true` on every poll so HA can ride the
  server's TTL cache instead of triggering full DDC/CI probes per entity.
- select / number entities now check the server's `success` flag and re-
  sync from the actual monitor state when a write was silently rejected
  (some monitors honor reads but ignore writes for certain DDC/CI codes).

Bumps manifest.json to 0.3.0 - the device topology change is user-visible
and existing brightness/power entities migrate to per-display devices on
first reload (unique_ids are preserved).

custom_components/remote_media_player/switch.py

@@ -5,14 +5,14 @@ from __future__ import annotations
 import logging
 from typing import Any
 
-from homeassistant.components.switch import SwitchEntity, SwitchDeviceClass
+from homeassistant.components.switch import SwitchDeviceClass, SwitchEntity
 from homeassistant.config_entries import ConfigEntry
 from homeassistant.core import HomeAssistant
-from homeassistant.helpers.entity import DeviceInfo
 from homeassistant.helpers.entity_platform import AddEntitiesCallback
 
 from .api_client import MediaServerClient, MediaServerError
 from .const import DOMAIN
+from .display_device import display_device_info
 
 _LOGGER = logging.getLogger(__name__)
 
@@ -51,6 +51,7 @@ class DisplayPowerSwitch(SwitchEntity):
 
     _attr_has_entity_name = True
     _attr_device_class = SwitchDeviceClass.SWITCH
+    _attr_name = "Power"
 
     def __init__(
         self,
@@ -62,33 +63,15 @@ class DisplayPowerSwitch(SwitchEntity):
         self._client = client
         self._entry = entry
         self._monitor_id: int = monitor["id"]
-        self._monitor_name: str = monitor.get("name", f"Monitor {monitor['id']}")
-        self._resolution: str | None = monitor.get("resolution")
         self._attr_is_on = monitor.get("power_on", True)
-
-        # Use resolution in name to disambiguate same-name monitors
-        display_name = self._monitor_name
-        if self._resolution:
-            display_name = f"{self._monitor_name} ({self._resolution})"
-
         self._attr_unique_id = f"{entry.entry_id}_display_power_{self._monitor_id}"
-        self._attr_name = f"Display {display_name} Power"
+        self._attr_device_info = display_device_info(entry, monitor)
 
     @property
     def icon(self) -> str:
         """Return icon based on power state."""
         return "mdi:monitor" if self._attr_is_on else "mdi:monitor-off"
 
-    @property
-    def device_info(self) -> DeviceInfo:
-        """Return device info."""
-        return DeviceInfo(
-            identifiers={(DOMAIN, self._entry.entry_id)},
-            name=self._entry.title,
-            manufacturer="Remote Media Player",
-            model="Media Server",
-        )
-
     async def async_turn_on(self, **kwargs: Any) -> None:
         """Turn the monitor on."""
         try: