Add display brightness and power control

- New display service with DDC/CI brightness and power control via screen_brightness_control and monitorcontrol
- New /api/display/* endpoints (monitors, brightness, power)
- Display tab in WebUI with per-monitor brightness sliders and power toggle
- EDID resolution parsing to distinguish same-name monitors
- Throttled brightness slider (50ms) matching volume control pattern

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

media_server/routes/__init__.py

@@ -3,8 +3,9 @@
 from .audio import router as audio_router
 from .browser import router as browser_router
 from .callbacks import router as callbacks_router
+from .display import router as display_router
 from .health import router as health_router
 from .media import router as media_router
 from .scripts import router as scripts_router
 
-__all__ = ["audio_router", "browser_router", "callbacks_router", "health_router", "media_router", "scripts_router"]
+__all__ = ["audio_router", "browser_router", "callbacks_router", "display_router", "health_router", "media_router", "scripts_router"]

media_server/routes/display.py

@@ -0,0 +1,59 @@
+"""Display brightness and power control API endpoints."""
+
+import logging
+
+from fastapi import APIRouter, Depends
+from pydantic import BaseModel, Field
+
+from ..auth import verify_token
+from ..services.display_service import (
+    get_brightness,
+    list_monitors,
+    set_brightness,
+    set_power,
+)
+
+logger = logging.getLogger(__name__)
+
+router = APIRouter(prefix="/api/display", tags=["display"])
+
+
+class BrightnessRequest(BaseModel):
+    brightness: int = Field(ge=0, le=100)
+
+
+class PowerRequest(BaseModel):
+    on: bool
+
+
+@router.get("/monitors")
+async def get_monitors(
+    refresh: bool = False, _: str = Depends(verify_token)
+) -> list[dict]:
+    """List all connected monitors with brightness and power info."""
+    monitors = list_monitors(force_refresh=refresh)
+    logger.debug("Found %d monitors", len(monitors))
+    return [m.to_dict() for m in monitors]
+
+
+@router.post("/brightness/{monitor_id}")
+async def set_monitor_brightness(
+    monitor_id: int, request: BrightnessRequest, _: str = Depends(verify_token)
+) -> dict:
+    """Set brightness for a specific monitor."""
+    success = set_brightness(monitor_id, request.brightness)
+    if success:
+        logger.info("Set monitor %d brightness to %d", monitor_id, request.brightness)
+    return {"success": success}
+
+
+@router.post("/power/{monitor_id}")
+async def set_monitor_power(
+    monitor_id: int, request: PowerRequest, _: str = Depends(verify_token)
+) -> dict:
+    """Turn a monitor on or off."""
+    action = "on" if request.on else "off"
+    success = set_power(monitor_id, request.on)
+    if success:
+        logger.info("Set monitor %d power %s", monitor_id, action)
+    return {"success": success}